Is Delta-8 THC Legal in Texas?
As more users begin enjoying delta-8 THC in the Lone Star State, many wonder how long this legal high can stay legal as the DEA closes in.
Delta-8 THC is arguably the most talked-about cannabinoid currently on the market today. It’s a variant or homolog of delta-9-THC capable of causing a mild-to-moderate high. Many are actually branding it “The New THC”. And that’s not even the best part. Delta-8-THC is the connection between federally legal hemp and federally illegal marijuana, acting as a federally legal high across many U.S. states.
However, legal highs (from cannabis or otherwise) have been strictly regulated or prohibited in the United States. Will delta-8 suffer the same fate? Will Texas see delta-8 prohibition?
Is delta-8 legal in Texas?
- Delta-8 THC is currently legal in Texas after Travis County judge temporarily blocked the state from classifying it as a controlled substance.
- A final trial set for January 2022 will make a decision on the case between Hometown Hero vs. DSHS.
- Under state law, hemp-derived delta-8 THC with less than 0.3% THC is legal to buy and sell.
- You are able to purchase, possess, and consume hemp-derived delta-8 products without landing yourself in trouble with Texan law enforcement.
- In 2020, the DEA issued an interim final rule addressing delta-8-THC’s legal status — believes it could be “synthetically-derived” and a controlled substance, making it federally illegal.
- Delta-8 isn’t naturally abundant in hemp plants. It requires manufacturers to convert CBD into delta-8. Some believe this conversion makes delta-8 a synthetic, while others don’t believe this is the case.
- If labeled a synthetic variant of THC, delta-8 could be outlawed and deemed illegal in the future.
Update on Delta-8 Legality in Texas
See a more comprehensive update on the delta-8 legal battle in Texas with a live timeline of events and answers to frequently asked questions.
Updated February 1, 2022:
A recent video release from Hometown Hero CEO Lukas Gilkey announces yet another huge win for the delta-8 legal battle in Texas: “The Texas Supreme Court denied DSHS’ request to hear our case. This means that our case stays in the Texas Appellate Court until our case is ruled on (6-12 months). This was DSHS’ best chance to win, and it was denied. Delta-8 THC remains legal in Texas!”
Updated November 8, 2021:
On November 8, 2021, the court granted Hometown Hero’s application for a temporary injunction which prohibits the “rule stated on DSHS’s website that Delta-8 THC in any concentration is considered a Schedule I controlled substance.” A final hearing of this case is set for January 2022.
As of November 8th, hemp-derived delta-8 THC (with less than 0.3% THC) is legal to buy and sell in Texas.
You can read the court’s new ruling in the case below.
Updated November 1, 2021:
Sky Marketing Corporation, which does business as Hometown Hero, is fighting back against Texas and its decision to ban delta-8 and categorize it as a schedule I controlled substance. The company filed a lawsuit in Travis County requesting a temporary restraining order (TRO) to block the ban but was rejected by State District Judge Gary Harger on October 22nd, 2021. A full court hearing is set for November 5th.
Hometown Hero’s CEO Lukas Gilkey recently posted a video on YouTube asking for other companies to file their own temporary restraining orders, as well as offering guidance and resources to vendors and retail stores affected by the ban.
Currently, Vape City, a Houston-based vape company with 75 retail stores across the US, and CBD American Shaman are the only other companies to file a similar lawsuit but have yet to receive a response.
As of writing this, the use, possession, sale, distribution, and production of hemp-derived delta-8 THC remain illegal in Texas.
Updated October 15, 2021:
Despite TX House Bill 2593 failing to ban delta-8 products, the Texas Department of State Health Service updated its website on October 15, 2021, claiming delta-8 is now prohibited in the Lone Star State.
According to the DSHS website, delta-8 in all concentrations and delta-9 above 0.3% are now controlled substances under Texas’ Controlled Substances Act. This means the use, possession, purchase, sale, distribution, and production of delta-8 products are strictly illegal and punishable under the state’s penal code.
Texas Department of State Health Services website was updated on October 15, 2021, claiming delta-8 is now prohibited.
Previously, delta-8 was presumed legal after Gov. Greg Abbott signed TX House Bill 1325 legalizing all hemp-derived compounds, provided they’re sourced from hemp plants carrying no more than 0.3%.
As of right now, delta-8 is a schedule I controlled substance in Texas, placing it alongside heroin, LSD, MDMA (ecstasy), and psilocybin as having no medical value and open to abuse.
Penalties for the use, possession, sale, distribution, and production of a schedule I controlled substance can result in imprisonment, a fine, or both.
CBD American Shaman and other companies are taking legal action against Texas.
Updated September 2021:
Recently, delta-8 THC’s legality in the state of Texas was hanging in the balance. State lawmakers attempted to brazenly ban delta-8 within an inch of its life, causing uproar in the Texan cannabis community.
Texas House Bill 2593, which sought to reduce criminal penalties for the possession of THC concentrates, was controversially amended during the Senate floor debate to limit the quantity of all tetrahydrocannabinols to 0.3% per product. This amendment would have made all products carrying above 0.3% delta-8 illegal under Texan law, resulting in a huge financial blow to delta-8 retailers and suppliers operating in the state.
Thankfully, the bill failed to pass and died in the legislature after a House conference committee removed the amendment and the Senate later failed to vote. This means the use, possession, production, sale, and distribution of delta-8 remains legal in Texas.
This amendment, which was later removed, would have banned all delta-8 products in Texas with more than 0.3% THC.
Is Delta-8 THC legal in Texas?
Hemp-derived Delta-8 THC is no longer legal in Texas. All hemp-derived cannabinoids, terpenes, flavonoids, and isomers are not allowed for sale, distribution, possession, and use. See the latest updates above.
How Texas falls in line with federal law
In 2018, the Trump administration signed the Agriculture Improvement Act (Farm Bill) into law, allowing the cultivation, production, distribution, possession, and use of hemp and hemp-derived products. It also removed all tetrahydrocannabinols in hemp (THCA, THCV, and delta-8 THC) from the list of controlled substances.
Previously, the federal government categorized all cannabis (including hemp) as a Schedule I controlled substance, deeming it illegal. The Farm Bill essentially differentiates between hemp and marijuana (medical cannabis).
Differentiating between hemp and marijuana
This differentiation is important — and it’s all to do with how much THC (still a controlled substance if above 0.3%) is present in the plant. Hemp typically carries less than 0.3% THC, while marijuana carries up to 15-20% THC on average. Because 0.3% is the legal limit, hemp is equally legal.
Due to hemp’s federally legal status, all plant hemp-derived compounds (minus THC) are totally legal, which includes delta 8. As mentioned, Texas follows this federal ruling and allows delta-8 THC to be sold, distributed, possessed, and consumed under state law.
According to Edna’s Unbaked CBD, a small but valuable Youtube channel hosted by its knowledgeable company CEO, an unnamed Texan law enforcement officer confirmed delta-8 THC is totally legal not only across the state of Texas but in most states across the US. Even the drug enforcement division told him delta 8 is legal under state law, simply because Texan law falls in line with federal law under the Farm Bill 2018.
And here’s the (kind of) bad news about delta-8 in Texas
Despite being federally legal under the 2018 Farm Bill, delta-8’s growing popularity as a “legal” hemp-derived high has caught the attention of the Drug Enforcement Administration (DEA).
In August 2020, the DEA issued an interim final rule seeking to address the status of delta-8 THC, which it believes is a “synthetically-derived” tetrahydrocannabinol analog and must be scheduled under the Controlled Substances Act (CSA) to comply with the 2018 Farm Bill.
The confusion surrounding the DEA’s 2020 ruling
The DEA’s rule doesn’t clearly define what it means by “synthetically-derived”, opening it up to interpretation and a whole lot of confusion, especially from cannabis brands currently selling delta-8 THC products in Texas and beyond.
The DEA could see delta 8 as a synthetically-created cannabinoid, placing it as a Schedule I controlled substance.
Since it’s a “minor” cannabinoid and only present in trace concentrations (up to 1%), hemp producers and manufacturers are converting CBD into delta-8 THC via an isomerization process. Isomerization simply means turning one isomer (CBD) into another isomer (delta-8) by altering the molecular structure but not adding or removing anything from it.
The devil’s in the definition
This is where the confusion comes in. Some believe the DEA is taking the dictionary meaning of “synthetic” and applying it here. The dictionary definition of synthetic is “relating to, or produced by chemical or biochemical synthesis.” If this is true, the synthesis of CBD to delta-8 THC may actually be an illegal practice.
However, others suggest “synthetically-derived” doesn’t apply here since neither hemp-derived CBD nor delta-8 is strictly a man-made chemical, and the isomerization of CBD to delta-8 doesn’t result in a synthetic compound. True synthetic cannabinoids (K2, Spice) are exclusively created in laboratories using only laboratory chemicals. No natural cannabis plants are used in the process.
So, right now? Delta-8 is federally legal under the 2018 Farm Bill but the process of turning CBD into delta-8 THC is under fire and fraught with contradictions. The DEA could see it as a synthetically-created cannabinoid, placing it as a Schedule I controlled substance.
How are companies getting around the law?
CBD and cannabis companies don’t have to “get around” the law, per se. It’s federally legal under the 2018 Farm Bill. They just have to be very careful with how they conduct business surrounding the production, manufacturing, and distribution of delta-8 THC products since the DEA got involved.
Many brands have enlisted the help of lawyers to make sure they’re not overstepping the mark and interpreting federal law, DEA ruling, the 2018 Farm Bill the wrong way.
Best Delta-8 products that deliver to Texas
If you’re looking to buy delta-8 (or hemp-derived delta-9) products online, here are the products we recommend. For more options, see our latest picks for the best delta 8 gummies, flower, and vape carts.
Manufacture or delivery of drugs: The criminal charges and possible penalties in Texas
Manufacture or delivery of drugs is the criminal charge for any form of drug dealing in Texas. The punishments can be much more severe than in simple possession cases if the amounts are large enough, with sentences of up to life in a Texas prison and fines up to a quarter-million dollars.
The Texas Controlled Substances Act defines “delivery” as giving a controlled substance, or a fake controlled substance, to another person. That means actually handing the drugs over to someone, or delivering them indirectly, such as by giving someone keys to a car with drugs in the trunk. In Texas, delivery is the same as selling drugs , whether money changes hands or not, except in the case of small amounts of marijuana.
Police can charge you with dealing drugs by using an undercover officer to take the delivery, by conducting surveillance on an exchange, or by getting a confidential informant to make the deal and testify to it later in court.
Make no mistake about it, if you are charged with manufacture or delivery of drugs in Texas, your freedom is at stake , and you will need the help of a good criminal defense lawyer.
First, an explanation of how illegal drugs are classified in Texas.
Drugs that are Illegal in Texas
The Texas Health and Safety Code divides controlled substances into five penalty groups, plus a marijuana category. They are:
Cocaine, heroin, methamphetamine, GHB, ketamine, oxycodone, and hydrocodone.
Ecstasy, PCP, and mescaline.
Valium, Xanax, and Ritalin.
Compounds containing Dionine, Motofen, Buprenorphine or Pryovalerone
Marijuana is defined in the health code as any Cannabis sativa plant, whether it is growing or not, the seeds of the plant and any preparation of the plant such as a joint or a package containing dried and shredded buds.
Texas Criminal Penalties for Dealing Drugs
As with simple possession laws in Texas, the punishments for manufacture or delivery of drugs vary according to the weight or amount of the drug. These are the punishments for the weights in the five penalty groups:
Drug Penalty Group 1
Less than one gram
State jail felony
180 days to 2 years in a state jail and/or a fine of not more than $10,000
1 gram or more, less than 4 grams
2 to 20 years in a state prison and/or a fine of not more than $10,000
4 grams or more, but less than 200 grams
5 to 99 years in a state prison and/or a fine of not more than $10,000
200 grams or more, but less than 400 grams
Enhanced first-degree felony
10 to 99 years in a state prison and/or a fine of not more than $100,000
400 grams or more
Enhanced first-degree felony
15 to 99 years and a fine of not more than $250,000
Drug Penalty Group 1A
Fewer than 20 units
State jail felony
180 days to 2 years in a state jail and/or a fine of not more than $10,000
20 or more units, but less than 80 units
2 to 20 years in a state prison and/or a fine of not more than $10,000
80 units or more, but less than 4,000 units
5 to 99 years in a state prison and/or a fine of not more than $10,000
4,000 units or more
Enhanced first-degree felony
15 to 99 years in a state prison and a fine of not more than $250,000
Drug Penalty Group 2
Less than one gram
State jail felony
180 days to 2 years in a state jail and/or a fine of not more than $10,000
1 gram or more, less than 4 grams
2 to 20 years in a state prison and/or a fine of not more than $10,000
4 grams or more, but less than 400 grams
5 to 99 years in a state prison and/or a fine of not more than $10,000
400 grams or more
Enhanced first-degree felony
10 to 99 years in a state prison and/or a fine of not more than $100,000
Drug Penalty Groups 3 and 4
Less than 28 grams
State jail felony
180 days to 2 years in a state jail and/or a fine of not more than $10,000
28 grams or more, but less than 200 grams
2 to 20 years in a state prison and/or a fine of not more than $10,000
200 grams or more, but less than 400 grams
5 to 99 years in a state prison and/or a fine of not more than $10,000
400 grams or more
Enhanced first-degree felony
10 to 99 years and a fine of not more than $100,000
Class B misdemeanor
Not more than 180 days in a county jail and/or a fine of not more than $2,000
Class A misdemeanor
Not more than 1 year in a county jail and/or a fine of not more than $4,000
More than ¼ ounces, but less than 5 pounds
State jail felony
180 days to 2 years in a state jail and/or a fine of not more than $10,000
More than 5 pounds, but less than 50 pounds
2 to 20 years in a state prison and/or a fine of not more than $10,000
More than 50 pounds, but less than 2,000
5 to 99 years in a state prison and/or a fine of not more than $10,000
More than 2,000 pounds
Enhanced first-degree felony
10 to 99 years and a fine of not more than $100,000
And there’s more, too. Spend or invest any of the money made from selling drugs, and that is another felony charge. Get arrested for dealing drugs within 1,000 feet of a school or youth center, on a school bus, or within 300 feet of a public swimming pool or video arcade, and the felony charge increases by one degree .
The Texas Code of Criminal Procedure also allows police to seize any property used or “intended to be used” in the commission of a drug felony. That means they can take your car, your home, or any other belonging where you are accused of carrying or hiding drugs. The asset forfeiture law is a civil action, not criminal, and you don’t have to be convicted for the state to try to take your property.
What happens if convicted of manufacture or delivery of drugs?
Like any case, the punishment for a conviction on drug dealing charges depends on your past history and the facts of the case, particularly the amount of drugs involved.
Community supervision is always an option for the judge or jury in cases with low drug weights, particularly on misdemeanors, state jail felonies and second-degree felonies.
However, the likelihood of prison time is high for a first-degree or enhanced first-degree felony . Even if you get community service on a state jail felony for delivery, the judge can still require that you spend three to six months in state jail as part of your sentence.
And you may not be eligible for community supervision at all if you’ve previously had charges enhanced under proximity-to-children provisions. In fact, in those cases, you may even have an additional five years added to the sentence.
To help you avoid a conviction and sentence in your manufacture or delivery case, we will attack the merits of the state’s evidence on several key points.
First, we may challenge the state’s identification of you as the person who made the delivery. We also will challenge the credibility of any confidential informants. And, we’ll challenge the legality of any police searches in case they violated your Fourth Amendment protections against unreasonable search and seizure.
Drug dealing is a very serious charge in Texas, but we will be there to make sure you have every chance at successfully defending yourself against it.
Frequently Asked Question Categories
Answer: Thank you for contacting the Denton County Master Gardener Help Desk with your question about treating your zoysiagrass for brown/large patch in October.
Brown patch, also known as Large patch, is a fungal disease (Rhizoctonia spp.) that is the most common and damaging disease of warm and cool-season grasses. Warm-season grasses most commonly affected are centipedegrass, zoysiagrass, and St. Augustinegrass. Bermudagrass is not as severely damaged. Its rapid growth allows Bermudagrass to recover more quickly. Brown/Large patch is most active in late fall in spring.
The symptoms appear as thin patches of light brown grass in rough circular shapes. Sometimes the center recovers, giving the diseased area a donut-shaped appearance.
To help you diagnose if your zoysiagrass is suffering from brown/large patch disease, look for yellow leaves at the edges of the patches. The leaf sheath will rot so that the leaf blade will separate easily from the runner with a gentle tug. For a specific diagnosis, send a sample to the Texas Plant Disease Diagnostic Lab using the form found at this link: https://plantclinic.tamu.edu/files/2010/10/Plant-Disease-Diagnosis-Form-D-1178.pdf.
Prevention & Control
The disease develops more in the following conditions:
- Applying fertilizer in late fall
- Poor drainage
- Watering too frequently
- Mowing lower than 2” to 3” high
- Heavy thatch
Brown/large patch is difficult to get rid of, so preventing the disease is critical. The first step to preventing brown patch is to eliminate any of the conditions that promote the development of the disease:
- Improve drainage in areas where the soil stays wet. A thin top dressing of compost applied in early spring will help drainage. If the soil is bare, amend it with 3″ of expanded shale and turn or till it in 6″ to 8″. Apply 3″ of compost on top. Redirect downspouts and check irrigation system zone settings to avoid overwatering poorly drained areas.
- Aerate the soil to decrease thatch.
- Water in the early morning to allow the leaf blades to dry during the day. And water only when needed.
- Avoid applying high nitrogen fertilizer in mid-to-late fall or early spring before the lawn fully greens up. Have your soil tested and apply fertilizer according to the recommendations. Click this link for step-by-step directions for having a soil test done: https://dcmga.com/north-texas-gardening/community-gardening/soil-testing/.
- Mow in the morning, after the dew has dried, and set the mower blade height to 2” to 3”. Avoid spreading the disease to other areas. In warm, moist weather, remove the clippings and mow the diseased areas last.
Fungicide treatments of warm-season grasses in the fall are crucial for best disease control. The first application should be made in October and repeated 2 to 4 weeks later. Reapply in April. Fungicides with these active ingredients are most effective: Azoxystrobin (with Propiconazole), Pyraclobstrobin (with Triticonazole), or Fluoxastrobin.
As always, carefully read and follow the cautions and instructions on the product label.
Your zoysiagrass may recover from a light brown patch infection as temperatures rise in the late spring or early summer. Resodding extensively damaged areas may be needed in the spring.
Learn more about brown/large patch at these web links:
“Brown Patch & Large Patch Diseases of Lawns”, Clemson Cooperative Extension
Question: Four brown rings about 5 ft around popped up in my lawn this week. Are these caused by chinch bugs? Is there any treatment for this? (June 4, 2021)
Answer: These mysterious rings are called Fairy Rings! They are caused by a fungal disease that eats decaying plant tissues. In medieval lore, they were thought to appear after fairies danced around in the area, hence the common name Fairy Ring.
What do Fairy Rings look like? Fairy Rings are circular, abnormal turfgrass growth. They usually appear in turf with high levels of organic matter and in areas where trees have recently been removed. The rings can be up to 15 feet in diameter. The texture and color of the turf are distinctly different from the surrounding area both inside and outside the ring. The turf can be brown and drier or much greener and denser than the surrounding turf. Sometimes, mushrooms may form on the edge of the ring, particularly in wet conditions.
Where do they come from? Fairy Ring disease is caused by fungi that feed on decaying organic matter such as tree stumps, logs, leaves, or roots. The fungi growth begins from the center and expands outward. There are three types of rings based on the conditions:
Type 1 The fungi produce compounds that reduce the soil’s absorption of water causing drought conditions. This leads to the turf browning and dying.
Type 2 As the fungi feeds on decaying organic matter it releases nitrogen causing lush growth and a dense green ring of turf.
Type 3 Rings of mushrooms grow around the edges of the ring during wet weather, particularly in the fall.
What should I do about the rings? Fortunately, Fairy Rings do not cause the turf to die. They are mostly a cosmetic issue. Typically, the rings will disappear naturally. There are a few prevention steps you can take:
- Aerate your turf to reduce the amount of thatch that the fungi feed on.
- Remove tree stumps, fallen limbs, and leaves from the lawn to reduce the amount of organic matter the fungi feed on.
- Topdress your lawn with a fine layer of sand to “dilute” the amount of organic matter in the lawn.
To reduce the distinctly different appearance of the ring, if it’s brown, use a soaker hose on the ring to soak the area so water reaches the roots. If the ring is greener than the surrounding lawn, fertilize the surrounding turf with a high nitrogen fertilizer to even up the color. Fungicides are not effective in the treatment or prevention of Fairy Rings so don’t waste your money or time on those. The bottom line, be patient and let the “fairies” that caused the rings move along on their own!
Learn more about Fairy Rings from this excellent article from the Wisconsin Horticulture Division of Extension weblink: https://hort.extension.wisc.edu/articles/fairy-rings/
Question: I live on the very east edge of Denton County, and want to know what type of Bermuda seed you could recommend to overseed my existing Bermuda. The variety I have “Builder’s Cheapest” grows fine, but never greens up. It gets plenty of water, lots of sun, and organic fertilizer, yet the results are mediocre. I would like to avoid laying new turf. Any suggestions are welcome! (February 12, 2021)
Answer: Thank you for contacting the Denton County Master Gardener Help Desk. Overseeding Bermudagrass is not difficult. Timing and preparation are important steps to ensure a good rate of germination. Here are the important steps and timing for our area:
Step 1 – February / March
Apply a pre-emergence herbicide for crabgrass, goosegrass, and other summer annual weeds. Timing of this step is critical and must be done when the soil temperature is cool and the summer annual weed seeds have not yet germinated.
Apply a post-emergence herbicide on cool-season weeds that are already growing in your lawn. Be careful to avoid overspray onto landscape plants you care about.
Request a soil analysis to help you understand what nutrients are needed for a healthy lawn. More information and the steps for requesting a soil analysis can be found at this link on the Denton County Master Gardener website: https://dcmga.com/north-texas-gardening/community-gardening/soil-testing/
Step 2 – April
Prepare the seedbed where you plan to overseed. First, dethatch the existing lawn with a vertical mower. Then aerate the soil, and, lastly top-dress with sandy loam. Vertical mowers and aeration devices can be rented for use.
Following the recommendations from your soil analysis, apply a starter-type fertilizer with an NPK ratio of about 1:2:1 (Nitrogen-Phosphorus-Potassium). Irrigate to settle the soil.
Step 3 – April / May
No earlier than April, or when the temperatures are consistently over 70 degrees F, overseed your lawn with a good quality Bermudagrass seed suitable for this area. Lightly rake the top-dressed soil to create ridges. This article from Texas A&M AgriLife will help you choose a suitable Bermudagrass variety, weblink: https://foragefax.tamu.edu/files/2013/05/E320.pdf
Thoroughly soak the soil, but not to the point of run-off. Water daily until the seeds germinate. Water less frequently, but thoroughly, after the seeds germinate.
Step 4 – Maintenance
Mow after the seedlings reach 2 to 3”, setting the mower blade height to 1 ½ to 2”. Sharpen your mower blades to avoid pulling up or damaging the seedlings. Apply a high-nitrogen fertilizer after mowing 2 to 3 times, usually not until late May / early June. It’s best to hand-dig weeds rather than using herbicides to avoid damaging the young seedlings. Water your lawn 1” weekly, absent rainfall, during the hot summer months. Apply a pre-emergence herbicide in September to suppress cool-season weeds, and again in late winter to suppress warm-season weeds.
This article from Texas A&M AgriLife has excellent step-by-step instructions for preparing the planting area and broadcasting seed, weblink: https://agrilifeextension.tamu.edu/library/landscaping/turfgrass-establishment-for-texas/.
Refer to this article from Texas A&M AgriLife for guidance on fertilizing warm-season turfgrasses in Texas, weblink: https://agrilifeextension.tamu.edu/library/landscaping/lawn-fertilization-for-texas-warm-season-grasses/.
Lastly, this article from Texas A&M AgriLife has a wonderful Bermudagrass home lawn management calendar that should help you know when to take which actions, weblink: https://agrilifeextension.tamu.edu/library/landscaping/bermudagrass-home-lawn-management-calendar/.
Question: Our lawn had a lot of roadside aster (weeds). We used an herbicide on it last month, and this past weekend pulled the dead weeds. A lot of dirt is now showing in the lawn. What cover is recommended to prevent weeds from settling there? Do we seed it with ryegrass or put turf down? (November6, 2020)
Answer: I’m glad to hear you’ve successfully removed the roadside aster from your lawn, and you’re right to be concerned about weeds germinating in the bare soil! I will include suggestions and links to help you decide which alternative would be best for you.
Ryegrass will green up quickly, but first, you’ll need to scalp the entire lawn so the seeds can reach the soil and germinate. Then, you’ll need to irrigate and mow all winter. In spring, you’ll still need to sod. (NOTE: If you already used a pre-emergent herbicide this fall, it will inhibit ryegrass germination, so you’ll definitely need to sod instead.)
Read below for the advantages and disadvantages of overseeding:
If it were me, I would prefer to put down sod now in the affected areas. If you choose this option, bear in mind that the new sod will not root well until next spring, so it will need to be watered carefully through the winter and early spring. (See link, below, for details.) An inexpensive soil moisture meter will help gauge whether irrigation is needed. You’ll only need to probe two to three inches into the soil, where the root zone is for this new turf. I would spot check moisture levels a couple of times per week when there’s been no rain. Remember, roots need oxygen as much as they need water, so make sure not to drown your sod, nor allow it to dry out for extended periods of time.
For information on managing sod planted in late fall (including irrigation), read “Maintaining New Sod” in this article:
When the grass exits dormancy in spring, the roots will begin to establish themselves in your soil. Thereafter, you’ll need to transition gradually into a standard (in this case, less frequent) watering schedule. Infrequent, deep watering of established turf coaxes roots deeper into the soil and protects the lawn from drought stress and problems caused by overwatering and frequent watering.
It will require patience, but long term, your best bet is a year-round routine for fertilization and weed control, using both chemical and mechanical methods. The following link offers detailed information:
This link will help you identify roadside aster in your turf:
Question: Our neighbor’s bamboo has started growing into our property. We cut it down with chain saws but wonder how we can stop it from growing back. I don’t think we can dig up the entire root system. Is there a legal herbicide you could recommend to control it? (October 23, 2020)
Answer: A perennial grass often planted for its ornamental value, bamboo has a dark side, as you’ve discovered. Surely the idiom “growing like a weed” was coined by someone battling bamboo!
There are two main types of bamboo, one growing slowly in a clumping habit and the other growing rapidly in a running habit. Safe to say that your bamboo is the running variety. The running rhizomes can spread up to five feet a year. You may need to employ simultaneously a number of control measures to beat back the bamboo, but it can be done.
Since you’ve already clear-cut the invaders, frequently mow any new leafy growth that appears. Leaves gain energy from the sun via photosynthesis and store that energy in the rhizomes. This stored fuel drives propagation. It is a slow process, but continual mowing of new growth will help deplete the rhizomes of the energy required to spread. Be prepared to mow for two to three growing seasons.
Another necessary control measure entails installation of an underground barrier to stop inevitable regrowth from the neighbor’s property. A barrier of concrete, treated wood, plastic or metal should be installed at a depth of at least 18 inches to deflect rhizome intrusion. Make sure the barrier extends at least two inches above grade, as those pesky rhizomes can spread at soil surface, as well.
For herbicide control, use a non-selective product containing the active ingredient, glyphosate. The chemical works by way of direct contact with leafy materials, so you’ll need to allow some regrowth for this method to work. Be warned: Just as with the mowing method, you should know that it may take two to three growing seasons to gain control with the herbicide. Please research each option for yourself and decide which of the two would be best for your situation.
If you choose to employ a herbicide, read and follow precisely the product’s instructions. In fact, read the product label completely before purchase so you can also buy any needed personal protective equipment (PPE). However tedious it might seem, use all PPE as instructed. After treatment, clean the clothes and PPE according to the label’s recommendation. Apply only when bamboo is actively growing and when rain is not anticipated in the 24 hours after treatment. Do not treat on a windy day, otherwise, overspray of the chemical can damage nearby plants. Saturate the leaves, but avoid runoff. Once the chemical is dry, people and pets can enter the treated area.
Refer to the links below for more details on how to wage war against bamboo:
Question: I have a section of my front yard that started getting grass burs a few summers ago. I have pulled them, overseeded, everything I can think of with the exception of killing the grass, and nothing gets rid of them. I am all organic and we do over-seed with ryegrass in the winter. I use Bermuda grass in the front yard and that section of the yard gets 8 hours of sun. I feel like that section of grass is just unhealthy. Will anything make them go away and never come back? (June 19, 2020)
Answer: Grassbur, also known as field sandbur (Cenchrus spinifex), is a summer annual grassy weed that grows in all types of soils and can be found in just about everywhere grass is growing: residential lawns, sports fields, parks and along roadsides. Grassbur has sharp, spiny burs that are part of their flower clusters. These burs seem to stick to and in everything and can be painful. It has a very long growing season, germinating in late spring and continuing to grow until the first killing frost in fall. It is a particularly pesky weed because they produce a lot of seeds that can lay dormant for a year or more before germinating. Because of this, grassbur cannot be eradicated in one season.
According to Texas A&M AgriLife Extension and University of Missouri Extension, here are the steps to controlling grassbur:
- Apply a pre-emergence herbicide between March 15 and April 1.
- In the case of heavy infestations, re-apply a pre-emergence herbicide every 6 weeks through September.
- Look for a pre-emergence herbicide labeled for sandbur control with one of these active ingredients: Pendimethalin, Benefin/Oryzalin, or Oryzalin. Pre-emergence herbicides must be watered in thoroughly to be effective. So, plan to apply just before a high probability of rain or irrigate the area after application.
- Note that pre-emergence herbicides inhibit the germination of grass seeds so follow the directions on the label for the timing of application if you plan to reseed your lawn.
- If you have grassbur germinate despite the application of a pre-emergence herbicide, spot treat with a post-emergence herbicide with the active ingredient MSMA or Fenoxaprop-ethyl. The post-emergence herbicide needs to be applied as a spray when the plants are young. Apply on a calm day, and carefully apply to the grassbur plants only to avoid killing your Bermuda grass. Tip: Make a shield around the nozzle of the sprayer by taping the cutoff top of a plastic soda bottle or milk jug around the nozzle.
- These steps will need to be repeated for several seasons to completely eradicate the grassbur seeds.
Organic and cultural controls include:
- Setting your mower blade to a low height, mow and bag the seed heads (burs) and discard them in the trash. This will need to be done every mowing through September for several seasons.
- According to the University of Hawaii, grassy weeds are particularly difficult to control organically. They recommend applying organic herbicides with active ingredients clove oil (eugenol), citric acid, and acetic acid to very young plants, thoroughly coating the leaves on hot, dry days. (Source website: https://www.ctahr.hawaii.edu/UHMG/downloads/Organic_weed_HG.pdf)
- Although not scientifically proven, some gardeners use corn gluten meal as an organic pre-emergence. Although, a study by North Carolina State University Extension indicated that corn gluten meal was not very effective as a pre-emergence herbicide for field sandburs. (Source website: https://ucanr.edu/sites/Grown_in_Marin/files/275912.pdf)
As with any chemical applied in the landscape, either organic or inorganic, read the label carefully for the suitability, directions for use, and follow all safety precautions.
The best defense for grassbur and other lawn weeds is a healthy lawn. It would be helpful to have a soil analysis done. The analysis will help you understand what nutrients your soil needs to grow healthy turf. Click on this link to learn about soil testing and the steps to have one completed: https://dcmga.com/north-texas-gardening/community-gardening/soil-testing/.
Question: My lawn is suffering, even though I follow Texas A&M guidelines on irrigation and fertilization. The turf gets 6 hours of sun daily. Would core aeration help? (June 5, 2020)
Answer: Core aeration involves removing plugs of soil from a landscape troubled by heavy, clay soil and/or compaction from foot traffic or construction. Turf needs oxygen as much as it needs water, so periodic core aeration advances the absorption of both elements. Topdressing with compost afterward further improves soil by adding microbes and nutrients to grow healthy roots, to discourage suffocating thatch, and to improve water infiltration.
To determine if your lawn would benefit from aeration, do a screwdriver test. Probe the suspect areas with a screwdriver; if you can’t easily penetrate the earth, you’ve got compacted soil and aeration will be beneficial.
Texas A&M recommends twice yearly core aeration of the most compacted areas of your lawn. This task should be done in the cool of the day during times of active turf growth, not during dormancy. (March and October) Soil needs to be somewhat moist for best results; waiting 24-hours after irrigation or significant rain should be sufficient. In contrast, do not aerate immediately after watering, otherwise, you can actually make the compaction worse.
For small areas, inexpensive manual aerators will do. For an entire lawn, consider renting a core aerator from a lawn and garden center or hiring a professional. Make sure to flag sprinkler heads so you don’t damage your irrigation system.
Immediately topdressing with ½” of fine compost and watering it in will allow the compost to filter down into the cores and get to work. The soil cores unearthed in the process can be allowed to disintegrate naturally, or if they are unsightly to you, simply rake them up.
Refer to these links for detailed information:
Excellent, brief publication on good turf management: https://aggieturf.tamu.edu/wp-content
Watch 27:00 to 30:00 in this video presentation given by Texas A&M Agrilife Extension horticulturalist David Rodriguez: https://youtu.be/tp6v5RzyzjM
Question: I’ve had trouble with brown patches in my St. Augustine grass. Is there anything I can do this winter to treat for it? (October 20, 2018)
Answer: Thank you for contacting the Denton County Master Gardener Help Desk with your question about treating your St. Augustine grass for brown patch this winter.
What is brown patch?
Brown patch, also known as Large patch, is a fungal disease (Rhizoctonia solani) that can infect both cool-season and warm-season grasses in North Texas. Symptoms on St. Augustine include circular or irregular brown patches which typically appear in the cooler months when evening temperatures are consistently below 68 o F, daytime temperatures are between 75 o F and 85 o F, and in wet conditions (Jo).
To help you diagnose if your St. Augustine is suffering from Brown patch disease look for yellow leaves at the edges of the patches. The leaf sheath will rot so the leaf blade will separate easily from the runner with a gentle tug (Jo). For a certain diagnosis send a sample to the Texas Plant Disease Diagnostic Lab using the form found at this link: https://plantclinic.tamu.edu/files/2010/10/Plant-Disease-Diagnosis-Form-D-1178.pdf.
Control & Management of brown patch
Your St. Augustine may recover from a light brown patch infection as temperatures rise in the late spring or early summer. Extensively damaged areas may need to be resodded in the spring.
The disease develops more in the following conditions:
- Applying fertilizer in late fall
- Poor drainage
- Watering too frequently
- Mowing lower than 2” to 3” high
- Heavy thatch
Prevention is Key
Brown patch is difficult to get rid of so preventing the disease is critical. The first step to preventing brown patch is to eliminate any of the conditions that promote the development of the disease:
- Improve drainage in areas where the soil stays wet. A thin top dressing of compost applied in early spring will help drainage. If the soil is bare, amend it with 3” of expanded shale and turn it in or till it in 6” to 8”. Apply 3” of compost on top of that (Welsh). Redirect downspouts and check irrigation system zone settings to avoid overwatering poorly drained areas.
- Aerate the soil to decrease thatch.
- Water only in the morning to allow the leaves to dry during the day. And, water only when needed.
- Fertilize with a high nitrogen fertilizer 6 weeks before the first frost which is typically mid-March in North Texas. Reapply fertilizer 3 weeks after the grass greens up in late spring.
- Set the mower blade height to 2” to 3”.
Fungicide effectiveness is limited once symptoms have appeared. It must be applied before or right after the first symptoms appear in October or November. This publication from Texas A&M AgriLife Extension lists fungicides registered for control of brown patch: How to Diagnose and Manage Large Patch Disease in Warm-Season Turfgrass. As always, carefully read and follow the cautions and instructions on the product label.
Sources & Resources
Jo, Ph.D., Young-Ki. “Brown Patch.” plantdiseasehandbook.tamu.edu, Texas AgriLife Extension, Texas Plant Disease Handbook, 31 May 2013, plantdiseasehandbook.tamu.edu/landscaping/lawn-turf/sorted-by-names-of-diseases/brown-patch/.
“D1178 – General Diagnostic Form and Instructions.” plantclinic.tamu.edu, Texas AgriLife Extension, Texas Plant Disease Diagnostic Lab, 1 Jun. 2017, plantclinic.tamu.edu/forms/d1178/.
Jo, Ph.D., Young-Ki. “How to Diagnose and Manage Large Patch Disease in Warm-Season Turfgrass.” https://cdn-ext.agnet.tamu.edu/, Texas A&M AgriLife Extension Service, 1 Feb. 2013, cdn-ext.agnet.tamu.edu/wp-content/uploads/2018/10/E-633-how-to-diagnose-and-manage-large-patch-disease-in-warm-season-turfgrass.pdf.
QUESTION: I am in eastern Wise County near Denton County line. We don’t have a master gardener listed on the website for Wise County, so I was hoping you could help.
I live in my grandparent’s old farmhouse with lawn carved from surrounding pasture. The lawn has never been “lush,” but I would like to improve it to lessen erosion and crowd out sandbur. I’m on well water, so please recommend drought-tolerant turf. Also, can I put ryegrass seed out now, to help with winter erosion, then follow in spring with a warm-season grass? (November 1, 2019)
ANSWER: DCMGA is the correct organization for Wise County residents, so we are happy to help. Although you didn’t mention the type of turf you currently have, the following should be helpful, regardless. First action I recommend is to send a soil sample to Texas A&M to see what your fertilization needs will be come spring. (Link below).
Buffalograss (Bouteloua dactyloides) would be the best warm-season grass for your situation. Buffalograss needs very little water once established. It requires full sun. You will not be able to seed buffalograss until May or June, however.
In the meantime, you can over-seed with ryegrass, if you wish. It will require regular irrigation to establish, then moderate winter irrigation. The best ryegrass variety for your situation is Panterra. In addition to looking pretty, it will help with runoff over winter, but will die out before you want to seed with buffalograss. However, if you prefer not to use well water in winter, simply wait until spring and seed buffalograss.
Before you seed in spring, you will need to prep your planting area. (Links below) You can be as strict about this as you want, but the most important steps would be scalping the existing turf, scarifying the soil so the seeds can land in loosened topsoil and carefully watering during the establishment. Once established, buffalograss is the most drought-tolerant grass for our area.
Question: Are there things I should do now, in August and September, to reduce the number of weeds and improve my lawn next year? I have a combination of St. Augustine in shady areas and Bermuda in sunny areas of my lawn. (September 11, 2020)
Southern crabgrass (Digitaria ciliaris)
Answer: You are a very smart gardener! As Confucius once said, “Success depends upon previous preparation, and without such preparation, there is sure to be failure.” There are several things you can do in August and September to have the lawn that is the envy of your neighbors next year.
- Water in the mornings to allow your lawns’ leaves to dry during the day. Lawns that stay wet over long periods are more susceptible to the development of diseases such as Large Patch Disease.
- Scale back on watering and fertilizing as the temperatures drop consistently below 70 o F and as your lawn stops actively growing.
- Mow frequently in August and September and bag/catch your clippings to capture annual weeds’ flowers and seeds. This will reduce their germination next spring.
- Overseed your lawn in the fall when the temperatures are consistently below 72 o
- Prepare your lawn to ensure good soil to seed contact by scalping the existing lawn, aerating or vertical mowing (removing thatch). A light top dressing with sand can also help ensure soil to seed contact.
- Follow the seed product labeling for watering to encourage seed germination. Light, frequent watering, often daily, will likely be needed.
- Read the product label carefully if you plan to apply a pre-emergence herbicide to understand which are safe to use for overseeding and the timing before and after overseeding.
- Pre-emergence herbicides are applied before weeds germinate. They inhibit or prevent the weeds from germinating. Post-emergence herbicides are applied after weeds have sprouted and are actively growing.
- Apply the appropriate pre-emergence herbicide for your lawn type and weeds your targeting to significantly reduce the number of annual weeds in your lawn.
- In the fall, apply pre-emergence herbicides in late August/early September. In spring, apply when the soil temperatures are between 50 o F and 55 o F, typically between mid-February and mid-March.
- Read the product label to understand the pre- and post-overseeding timing. As noted earlier, pre-emergence herbicides can prevent grass seed from germinating.
- Know what weeds you’re targeting and choose the product with the active ingredient(s) that target those weeds. Active ingredients dithiopyr, isoxaben, pendimethalin all target grassy weeds and some broadleaf weeds.
- Always read the entire product label before use and follow the instructions carefully.
Sources and Resources
Texas A&M AgriLife Extension
Question: This heat is frying my zoysia grass, which I put in last year. How many times a week should I water and at what time of day?
Answer: A great choice north Texas, zoysia grass has a superpower that may trick you into thinking the grass is “frying.” When faced with drought conditions, zoysia enters a type of dormancy. This defense mechanism allows it to preserve its precious roots, but in the process, its blades will take on a dry, grayish cast. Turf growth will slow down, as well. With zoysia, this response is normal, and provided you’ve taken reasonable care of your turf, it should perk back up when the heat and drought conditions decrease.
You asked about watering frequency. Deep, infrequent watering promotes healthier turf. The deep moisture coaxes roots into anchoring further into the life-giving soil. In general, your goal should be to dampen the top six inches of soil each time you water, which is about ½” to 1” of irrigation. Many variables affect how long it takes to achieve the goal, such as soil traits, sprinkler head types, humidity, wind, as well as recent temperatures and rainfall. Much of Denton County residents have clay to clay/loam soils. Clay is a sluggish absorber, so using a cycle-and-soak watering method is required to reach the six-inch depth without runoff. (See link, below, for details.)
Regarding what time of day to water, very early morning is optimum. Minimal wind in the early morning allows more of the water to reach its destination. Lower air temperature and higher humidity lessen simple evaporation. Simultaneously, early morning watering protects against fungal infestation, in that the grass blades dry well before nightfall when conditions are greatest for fungal growth.
With early morning watering, you might not notice a broken sprinkler head or split drip line. Each spring, inspect your irrigation system and make repairs accordingly. Some cities offer free irrigation check-ups where a licensed city irrigator will do the inspection for you, noting repairs you’ll be responsible for completing.
Cycle-and-soak watering method
Question: We moved to Denton County two years ago and have not been able to keep up with the weeds in our bermudagrass lawn. In all the years of caring for our lawns in other states, we’ve never had this much trouble. Our neighbors said we needed to hire a professional, but we can’t afford it. Can you help us?
Answer: Lawn weeds vex many people new to North Texas, but I assure you, with planning and patience, you can tackle this common problem on your own. No need for a professional! Twice yearly applications of pre-emergent herbicides and timely usage of post-emergent herbicides should remedy your weed problem in time.
In late winter, pre-emergent herbicides should be used 1 to 2 weeks before the average date of our last killing freeze, which is March 18. (You’ll need to move fast to get this round of herbicide down.) Then again in the last week of August or first week of September, a second round of pre-emergent is necessary for treating the cool-season weeds.
Post-emergent herbicides are most effective on young weeds, so they should be applied to warm-season weeds in late May or early June and to cool-season weeds in late October or early November. Aggie Turf provides details on these herbicides, as well as a wealth of science-based information on responsible lawn management, in general.
Question: Is it okay to apply a 3 in 1 fertilizer to my lawn in February?
Answer: We do not recommend weed and feed type products in general because the right time to apply these chemicals is different. A pre-emergent and post-emergent for winter weeds can be applied from mid-February through early March. Be sure to read the package label if you have St. Augustine grass because it is sensitive to some chemicals often found in pre- and post-emergent weed killers. Bermuda is more tolerant. Texas A&M AgriLife recommends having your soil tested before applying fertilizer as healthy, established lawns may not need it. If your lawn does need to be fertilized, it is best to wait until it is actively growing usually after you have mowed two or three times. Here is further guidance from Aggie-Turf for Bermuda and St. Augustine:
Question: My yard is crawling with army worms! I can literally see it moving. What can I do? (September 21, 2018)
Answer: The conditions are perfect for army worms this year, and they are marching across the county. Unfortunately, you may not notice them until they are mature, and by then they can consume an area as big as a football field in two or three days. They feed on the leaves, not the roots, so plants can recover. Bermudagrass is usually okay because it grows so aggressively, but some grasses may die. If there is significant damage, you should treat as soon as possible.
The threshold level for treatment is more than five larvae per square yard. There are many treatment options. If you want an organic option, you can use Bt (Bacillus thuringiensis) or spinosad. This article details each option in order of effectiveness and degree of harm to honeybees and the environment.
Question: I have a very old post oak that is declining. Where can I send a sample to be tested for disease? (September 7, 2018)
Answer: You have some options. First, you can send pictures to the Help Desk at [email protected] Sometimes we can see signs of fungus or another disease.
Second, you can bring us samples at 400 W. Hickory in Denton. Third, and in this case probably the best option, you can send samples to Texas A&M Plant Disease Diagnostic Lab. Look for forms and instructions at plantclinic.tamu.edu. It will cost a minimum of $35, but they will look at it under a microscope and be able to tell you if there is a disease process at work.
If your tree needs treatment, you can find a certified arborist at isa-arbor.com.
Question: When I drive along the boulevards in my city, I see new trees surrounded by huge mounds of mulch. Should I be using this much? (August 3, 2018)
Answer: Mulch is very important during summer in Texas to reduce water loss from the soil and to moderate soil temperature. In addition, if you use an organic source (e.g., leaves, grass clippings, wood chips) for your mulch, it will slowly break down and enrich your soil.
You can, however, use too much of a good thing. The thick piles you see are called volcano mounds and are not good practice. Tree roots need oxygen, and piling mulch a foot deep is similar to covering your nose and mouth. You wouldn’t last long, and neither will the tree! Spread mulch no more than 3-4” deep, and rake it a few inches away from the trunk. The same goes for all plants; keep the mulch away from the stems.
For more information and discussion of different types of mulch
Question. Moles are tearing up my yard! What can I do? (July 27, 2018)
Answer: They are eating grubs and aerating your soil, but most people do not find that sufficient reason to keep them around. The first thing to know is that most repellents do not work. You need a mole trap.
You also need your wits, however, because you need to think like a mole to trap one. They use some tunnels more frequently than others. Think of it as the difference between a highway and a side road. Finding an active runway is key. How do you know which tunnel is active? Step on it at night. If it is active, the mole will dig through it that night, and it will be raised up in the morning. That’s where the trap goes, and your chances of catching the critter go up. Details and a discussion of various types of traps
Question: The guy who cuts my grass told me to run each irrigation station 10 minutes three times a week, but my grass looks pitiful.
Answer: There are many variables, such as the type of grass, type of soil, amount of rainfall, the flow rate of your sprinklers, etc. The goal is to dampen the soil about 6” deep. This means you need to apply about 1/2-1” each time you water. The easiest way to find out how long it takes your system (manual or automatic) to water one inch is to place flat bottom cans in different locations around the yard. Run your system 30 minutes and measure how much water is in the can. Let’s say it’s 1/2”. Allow the water to soak in for about an hour and then take a long screwdriver and push it into the soil until it stops. If the soil is damp up to 3” deep, then you need to run your system another 30 minutes. If it goes easily into the soil the entire 6”, then you have watered enough. On heavy clay, watering once a week is probably enough. On sandy soils, you may have to water every 5-6 days. Watering more frequently and shallowly will cause the grass to have shallow roots, which is not what you want for healthy grass.
Question: My lawn guy says he thinks my grass has TARR (take-all-root-rot). Can you tell me about it and tell me how to cure it?
Answer: Moist spots in stressed grass are more likely to see this fungus in late spring or early summer. Before treatment, be sure you have TARR (take all root rot) rather than two look-alikes: brown patch (a different fungus) or chinch bugs, which are also active in the summer. Each one is treated differently. This article details diagnosis as well as treatment options for each condition.
TARR treatment includes lowering the pH, which can be accomplished with applications of peat moss a couple of times a year, and fungicides in the spring and fall. Preventive measures include improving drainage and aeration, reducing thatch, and watering infrequently but deeply.
Irrigation mistakes are extremely common and account for many instances of fungus and other diseases. Next week we will address how to irrigate your lawn properly.
Question: How can I get grass to grow under my trees? (April 23, 2021)
Answer: The short answer is that you can’t. Grass needs at least six hours of sunlight a day, and your thinning bare patches, particularly near the trunk, prove it. Our most shade tolerant grass is St. Augustine, but even it will not grow in dense shade. Some fescues are shade tolerant and cold hardy. However, they require a lot of water during the summer, and even they will not tolerate heavy shade.
You could cut down your trees and grow grass, but your property would suffer a loss of value, and your electric bill would probably go up. Your choices are to (a) prune your tree to allow more sunlight (remembering that leaves provide nutrition for the tree, so leave some!) or (b) use a shade-tolerant groundcover.
Question: When should I apply pre-emergent herbicides to my lawn?
Answer: Apply in early spring (late February-mid March) for summer weeds. Apply in early-mid September for winter weeds. Pre-emergents work by preventing seeds from germinating, so the weeds you see now have already germinated, and a pre-emergent will not work. You can apply a post-emergent weed killer for weeds that have already appeared. But be careful. There are different types of herbicides. Some are targeted to a particular plant (selective herbicide), whereas others kill every plant contacted (nonselective herbicide). For instance, if you apply a grassy weed killer in dormant grass, it might affect the grass you wanted to keep. St. Augustine grass is particularly sensitive to herbicides. Read the label, and never apply more than the recommended rate.
Question: I just moved to a new house. I have no idea how to take care of the lawn.
Answer: The Aggie Turf website has more information that you probably want about lawn care, including selection, establishment, fertilization, watering, etc. Since you are not familiar with the soil, first get the soil tested. For information about how and where to send a soil sample, see the Texas A&M AgriLife Soil, Water and Forage Testing Laboratory page.
Question: My St. Augustine grass is looking really bad.
Answer: St. Augustine has been beset by problems this year. Last year’s extreme cold was very stressful, and the extreme heat of summer combined with high humidity added more stress. The cold followed by heat and humidity is the perfect environment for fungi. Watch for gray leaf spot which shows up as brown lesions on the leaf. To reduce the severity of gray leaf spot, avoid applications of soluble nitrogen fertilizers on moderately shaded lawns during summer months. Herbicide applications which may weaken St. Augustinegrass should also be avoided on shaded lawns. Apply water to the lawn in early morning only when water is needed. Avoid late afternoon and evening watering which keeps the leaf surface moist for long periods. Also, catch grass clippings in lawns where gray leaf spot is a problem.
Also watch for brown patch, which forms circular brown patches. If you want a definite diagnosis, you can send a sample to the Texas Plant Disease Diagnostic Lab. For a fee, they will diagnose your ailing plants.
Question: Feral hogs rooted up my lawn and left a huge muddy mess. Can I overseed now with rye (November)?
Answer: You can, although overseeding is not usually recommended due to its competition with the warm season grass the following spring/summer. In your case, it might be best to control erosion during the winter. The option, although expensive, would be to sod with the grass of your choice.
Question: This will be my second year growing a vegetable garden. Last year’s crops were not as productive as I had hoped and a friend suggested the problem might be not enough bees came to visit the garden to pollinate the plants. I read that flowers in the garden will help attract bees. Any recommendations on what flowers bees like best? (January 28, 2022)
Answer: Great question! Bees are important pollinators for our garden plants along with butterflies, wasps and even bats. When we think of bees, we are often thinking about the European honey bee. But in North Texas, we have hundreds of species of Native Bees that can also be helpful pollinators for our vegetable garden. (http://w3.biosci.utexas.edu/jha/wp-content/uploads//Texas-Native-Bee-Families.pdf)
To encourage more bee visitors to your garden, it helps to think like a bee. So, what do bees look for?
- Layout: Bees are more likely to find flowers that are in groups. So, adding a 3×3 foot flower area is more noticeable to a bee than single plants distributed throughout the garden.
- Timing: Plants that are in flower at the same time as your spring or fall vegetable plants. (FYI: not all vegetables grown in North Texas home gardens require pollination by insects. Tomato plants have male and female flowers and can self-pollinate, usually aided by a bit of wind. Salad greens do not need pollination.)
- Color: According to the New York Botanical Garden, “Bees do not see color the same way humans do, so they are attracted to certain flower colors. Plants on the blue and yellow end of the color spectrum attract bees because those are the colors they can easily perceive. Darker colors such as red appear black to bees, and since black is the absence of color bees are not naturally attracted to plants with red hues. Also, some tubular flowers are not attractive to bees because the shape is not conducive to pollination. Choosing red plants will discourage bees in the garden.” https://libanswers.nybg.org/faq/222585#:
If you have problems or questions about plants in your landscape, DCMGA’s Help Desk is here for you. Contact us: https://dcmga.com/north-texas-gardening/help-desk/
More info on bees for your plants:
Question: We would like to add a couple fruit trees to our landscape. Can you recommend any that would be productive in North Texas? (December 31, 2021)
Answer: You have a chosen a great time of year to plant a new tree. Planting in January through March gives the tree time to adjust and spread its root system before the hot summer weather. While many varieties of fruit and nut trees can be grown in our region, some of the more successful fruiting trees include figs, peaches and plums. Most varieties of peaches and figs are self-pollinating, so you do not need to plant a second variety.
Dr. George Ray McEachern, fruit and pecan specialist with Texas A&M in an interview with horticulturist Neil Sperry suggested these varieties (https://neilsperry.com/2016/02/best-fruit-varieties-for-north-and-northeast-texas/):
- Figs: Alma variety. (Other choice: Celeste) Dr. McEachern has reevaluated winter hardiness of Alma, and feels it is equal to that of Celeste. According to Dr. McEachern, “Texas Everbearing/Brown Turkey exists in too many variations and is no longer recommended.”
- Peaches: Redglobe
- Plums: “Methley plum, a good pollinator, both for itself and for other plum varieties.” Although Methley plum is self-pollinating, you will get a better yield by having other Japanese plum trees nearby.
- In the interview referenced above, Dr. McEachern makes some varietal suggestions for other fruit bearing trees and shrubs.
For even more information on varieties of fruits and nuts and potential challenges, bookmark the AgriLife page on Fruit and Nut Resources, which has over 40 detailed fact sheets: https://aggie-horticulture.tamu.edu/fruit-nut/.
A selection of fruit and nut trees should be currently available at area nurseries soon. So, a couple more bits of advice: When purchasing a container-grown tree, check to ensure the roots are not girdled (tightly circling the trunk or other main roots) in the pot. “Texas Tree Planting Guide” has useful information on selecting a healthy nursery tree: https://texastreeplanting.tamu.edu/PickTreeAtNursery.html
Fruit and nut trees need at least six hours of sun for quality production, so choose a sunny spot with good drainage. A common planting mistake is to dig the hole too deep; a good rule of thumb is to dig the hole twice as wide as the root ball but at an equal depth, so the root flare (where the main roots meet the trunk) is not smothered and the root system has space to stretch and grow.
If you’re planting a container-grown tree, gently separate the roots and remove any excess soil covering the top of the root ball. Backfill the hole’s interior circumference with native soil, and water well. Continue to water regularly as the new planting establishes itself in the new location. Be sure to remove weeds and grass from the soil surrounding the new planting and keep the area clear for about five years to reduce the competition for water and nutrients. Here’s a handy tree-planting guide: “Plant fruit trees the AgriLife Extension way” (https://agrilifetoday.tamu.edu/2020/10/23/plant-fruit-trees-the-agrilife-extension-way/).
Earth-Kind Landscaping, offers this general tree planting instruction guide, “Planting a Tree” https://aggie-horticulture.tamu.edu/earthkind/landscape/planting-a-tree/.
Question: My plum tree has lots of fruit, however, several of them are shriveled, brown and mushy. My neighbor’s tree has the same issue. What’s wrong? Is there anything I can do to keep the problem from spreading? (July 2, 2021)
Answer: Your plum tree looks beautiful with plenty of fruit, although it appears that some of the fruit on your tree and your neighbor’s tree has brown rot (Monilinia spp.) This is a fungal disease that is commonly found in stone fruit (cherries, apricots, peaches, and plums). In the U.S., the species that is found most often is Monilinia fructicola. This disease can also cause blossom blight and stem canker.
The high humidity, rainfall, and heat we’ve experienced this spring and early summer promote the development of the disease. Several steps can be taken to respond to and prevent the disease.
Where Does Brown Rot Come From?
Monilinia fructicola was present in your tree’s twigs and fruit from the previous year. In the spring the rainfall and wind spread the spores infecting the flowers causing them to turn black. The dying tissue will have brown and tan spores on them. Once you see this, the likelihood of the fruit being infected is very high. As the fruit grows and ripens, the fungal disease grows as well causing the damage to be most apparent at harvest time.
What Does Brown Rot Look Like?
The fruit’s surface will have tan and brown circular lesions. As the fungal spores grow, the lesions will get larger and sometimes appear in concentric circles. Eventually, the fruit will completely rot and dry up, sometimes referred to as “mummy fruit”. The dead fruit may cling to the branch or fall to the ground.
The fungal disease can spread from the infected fruit to the twigs. The infected twigs will have dark, depressed cankers in an elliptical shape. As the disease progresses it cuts off the flow of water and nutrients. Brown rot overwinters in the infected twigs, leaves, and fruit that remain on the tree continuing the cycle of the disease into the next year.
What Can Be Done Right Now?
- Remove and discard infected fruit, both on the tree and the ground. Do not compost the fruit, put it in the trash.
- Prune away infected twigs and branches. Again, do not compost them. Sanitize the tool you use to prune between each cut. I know this sounds like a hassle; however, it will help to limit the spread of the disease. I take a handful of disinfecting wipes with me when I prune to wipe down the cutting blades between cuts.
- Thin out any crossing branches and fruit that touch one another to improve air circulation and limit the spread of the disease from one fruit to another.
- Pick up and discard any fruit or branches on the ground.
How Can I Prevent Brown Rot Next Year?
In addition to pruning and discarding infected twigs, branches, and fruit, the application of a fungicide product labeled for Brown Rot will help prevent the disease. As with many diseases, Monilinia fructicola outsmarts us by developing resistance to fungicides. To reduce that risk, alternate between the active ingredients in the fungicide you apply using the Fungicide Resistance Action Committee (FRAC Code) table below (The FRAC Code should appear on the product label). For example, apply a fungicide from the FRAC 1 group this season and the FRAC 3 group next season.
- The first application should be just before bloom when the buds begin to show a little pink.
- Apply fungicide again during bloom and just before harvest.
- Depending on the degree of infection and weather conditions (humid, hot), apply fungicide again throughout the season.
Always carefully read the product label and follow the application and safety precautions.
Fungicides Labeled for Brown Rot by FRAC Code
Maybe you and your neighbor could each purchase fungicides from different FRAC Codes and swap each season. Best of luck to both of you!
To learn more about Brown Rot (Monilinia fructicola) click on these web links from Texas A&M AgriLife Extension:
Question: Something is attacking my tomatoes! Damage is to the fruit, but not the leaves. So far only a few tomatoes have been affected. See attached picture. Should I spray them with a pesticide or Neem oil anyway even if I can’t see any bugs? (June 24, 2021)
Answer: It looks like your tomatoes have been damaged by a combination of too much exposure to direct sunlight and high temperatures. The problem is called sunscald. According to the University of Illinois, “Sunscald, a noninfectious disease of pepper and tomato, is caused by sudden exposure of the fruit to intense direct sunlight and is most serious during periods of extreme heat.” Sunscald often happens when there is insufficient foliage to protect the fruit from the direct rays of the sun. Once the fruit is damaged, it may make the plant vulnerable to disease.
What to do: remove the damaged tomatoes. You can check for taste if you choose, but it is unlikely that they will be edible. One action you can take is adding a canopy to help protect other vulnerable tomatoes and peppers using a special-purpose shade cloth available at nurseries and garden centers. Shade cloth is usually made of loosely woven polyester and is available in varying densities or degrees of shade protection from approximately 5% to 95%. Select a variety that is close to a 50% shade density.
An easy way to add shade is to build a hoop house and cover it with shade cloth. An added benefit: once you have the basic materials, you can also cover the hoop house in early spring or late fall with frost cloth to protect plants from cold. Be sure to read the packaging description on the shade and frost cloth to find out how much protection it offers your plants.
Building a quick and easy hoop house (see how-to video, link below): Materials: 18-inch rebar pieces, ½-inch PCV pipes, shade cloth, and something to hold or weigh down the cloth.
- Measure the size of the area to be covered and purchase rebar, PCV pipes (they come in 10 foot or 20-foot length sections) and shade cloth (enough to cover the width and length of you shaded area).
- Beginning on one side, push a piece of rebar into the ground leaving 6 inches of rebar above the soil. Add rebar pieces about 2 feet apart for the length of the area to be covered.
- Add rebar pieces to the other side opposite of the first set of rebar.
- Push PCV pipe over rebar on one side, bend in the middle to get the desired height and insert over opposite side’s rebar.
- Add cover, hold in place with clips and secure with weights at the bottom.
From Bonnie Plants, a short how-to video on making a hoop house: https://www.youtube.com/watch?v=rRpC-zjFUNs
More info on sunscald:
Question: I am new to vegetable gardening and I am so excited that my plants have started to put on tomatoes. How do I protect them so I get a good harvest? (5/21/2021)
Answer: Congratulations! Seeing the results of your hard work is rewarding. Did you know that tomatoes are the most popular home garden crop in Texas? Although there can be some challenges to getting from seedling to harvest, it is worth the effort. So, what bad things can happen and how should you protect your plants?
Common diseases that affect tomato plants: The list of potential diseases that can impact your tomato plants may seem daunting, but for most problems there are preventive or treatment options. Plant diseases are usually divided into categories based on the causal agent—fungal, bacterial and viral:
Fungal problems often begin with too much moisture creating an environment that fungi exploit. There is early blight, late blight, gray leaf spot, anthracnose, wilt, leaf mold, and buckeye rot as examples. Spots on the leaves are often the first sign of a fungus attacking your plant and are most likely to occur when water remains on the leaves for an extended period of time or the humidity is high. To protect your plants from fungal infections, you can take some preventive actions:
- Clip off any lower leaves that are touching the ground.
- Make sure your plants are spaced far enough apart to allow good airflow that will help to remove moisture from the leaves.
- Put about 3-inches of mulch around, but not touching, your plants so that water moves down into the soil while the mulch, with its larger particles, can dry quickly.
- Water plants in the early morning so that there is plenty of time for sun drying.
- Always sterilize your tools and gardening gloves after using them.
- You may choose to practice preventive control with an organic or chemical fungicide.
Bacterial problems for tomatoes include bacterial spot and bacterial canker. These problems can be difficult to control once they attack your plants so it is a best practice to buy disease-free seeds and seedlings.
Virus culprits include tobacco mosaic, double streak, spotted wilt and curley top. Because these virus infections are often caused when the plant is touched by contaminated hands or tools, you can limit the exposure of your plants by washing your hands before touching plants and making sure your tools are cleaned after use. Tomato plants exhibiting symptoms of a virus infection should be removed to protect nearby plants.
For detailed descriptive information on tomato plant disease problems and treatment, refer to the Texas Plant Disease Handbook list on tomatoes. https://plantdiseasehandbook.tamu.edu/food-crops/vegetable-crops/tomato/
Dealing with insect pests: Your North Texas tomato plants are desired food sources for caterpillars, whiteflies, hornworms, aphids and leafooted bugs to name a few. “In a home garden, handpicking and destroying many pests is an effective control measure. In addition, beneficial insects are very helpful in controlling insects such as aphids, leafminers and hornworms. To avoid killing these beneficials, use insecticides only when necessary.” (Clemson University Home and Garden Information Center)
Insecticides effectively control stink bugs, leaf-footed bugs, aphids, fruitworms, and hornworms. Bacillus thuringiensis (Bt) is an organic product that controls caterpillars and Bt products, such as Dipel (dust) and Thuricide (liquid concentrate), are effective in the control of hornworms and tomato fruitworms. Other organic pesticides include: Spinosad to control caterpillars and thrips, Pyrethrin for aphids and Neem oil for whiteflies.
Caution: Pollinating insects, such as honey bees and bumblebees, can be adversely affected by pesticides. Always spray late in the evening to reduce the direct impact on pollinating insects.
This presentation from the University of Connecticut provides pictures and damage descriptions to help you identify tomato diseases and pests in your garden: http://ipm.uconn.edu/documents/documents/App-TomatoPestIdentification3.pdf
Other tomato thieves: Birds, rodents and other critters find your tomatoes to be an excellent food source. Often pecking holes in several or just taking a bite out of one and then moving on to take a bite out of another.
To deter birds and small animals, you can place netting over your plants, which makes it difficult for birds, squirrels and rats to get to your tomatoes. It also makes it more difficult for you to harvest them, though. A good perimeter fence can help keep out larger animals. There are also repellents that be sprayed on plants or spread around them. These repellents are species specific. The University of Massachusetts offers this helpful information: “Excluding and Repelling Problem Wildlife from the Garden”.
Here’s a secret solution for dealing with tomato thieves: Pick your tomatoes early! When a tomato reaches its mature size and begins to lighten in color (about half green and half pink), it is okay to pick it. This is called the breaker stage. Allow the tomato to complete the ripening process off the vine. It does not need to be in a sunny window to ripen as the fruit has all that it needs to complete the transition from raw to fully ripe and ready to eat with no loss of flavor.
Question: I would like to grow potatoes but don’t have a lot of space. Can they be grown in a container? Also, what varieties are best? (March 12, 2021)
Answer: Many different vegetables can be grown in containers, and potatoes are one of them. In addition to saving space, container-grown potatoes reduce soil-borne pests and there’s no need to rotate crops.
Choosing the Best Variety
Potatoes are grown from seed potatoes which are tubers used to grow new potatoes. They should have several “eyes” which are small dimpled areas that contain vegetative buds. Do not try to grow potatoes purchased from the grocery store because they are treated to prevent sprouting. Purchase seed potatoes 2 to 3 weeks before the planned planting date from a reputable farm or feed store or online. Look for certified disease and fungus-free seed potatoes that are blight resistant.
According to the Texas A&M AgriLife Vegetable Variety Selector, good potato varieties for Denton County with days to harvest include:
All Blue (90 days): Heirloom, deep blue skin, blue flesh
Caribou (95 days): Russet, heat, and drought-tolerant, high yields
Désirée (95 days): Red skin, yellow flesh, drought-tolerant, disease-resistant
Kennebec (80 days): Buff skin, white flesh, medium-to-late maturing
Norland (80 days): Red skin, white flesh, early maturing
Red La Soda (100 days): Deep red skin, white flesh
Russian Banana (90 days): Heirloom, fingerling, yellow skin, golden flesh
Cobbler (80 days): Buff skin, white flesh, early season
Yukon Gold (90 days): Yellow-white skin, light-yellow flesh
Types of Containers and Soil
Many types of containers are suitable for growing potatoes.
- 10 – 15-gallon capacity, 24 to 36 inches tall. Avoid containers taller than 36 inches to ensure even moisture from the top to bottom of the container.
- Must have good drainage such as holes in the bottom.
- Materials include wood, metal, plastic, ceramic/clay, or heavy-duty fabric. Note that fabric containers dry out quickly and will need to be checked for adequate moisture more often.
The type of soil used for growing vegetables in containers is important. Soilless or synthetic potting mixes are best for container growing. Their ingredients include sawdust, wood chips, peat moss, perlite, or vermiculite. They are free of disease and weed seeds, drain well, hold moisture and nutrients well, and are lightweight. On the label look for “formulated for container gardening”.
Preparing and Planting
One to two days before planting begin to prepare the seed potatoes. Large seed potatoes should be cut into several pieces, each with several “eyes”. Lay the cut pieces on a tray to air dry for 24 to 48 hours to minimize rotting. Small fingerling potatoes do not require drying and can be planted whole.
On planting day, add 3 to 4 inches of potting mix to the container, mixing in a handful of starter fertilizer. Place several seed potato pieces or small fingerling potatoes around the bottom of the container. Cover with 4 to 6” of potting mix and water well.
Hilling, Watering, and Fertilizing
As the plants grow, “hill” the plants by adding more potting mix to the container, leaving about 3 inches of the foliage above the soil. Straw, hay, partially composted leaves, or regular compost can also be used for hilling. Add a handful of vegetable fertilizer into the hilling mix each time. Continue hilling the plants until the container is filled.
Keep your potato plants well-watered, one to two times weekly in hot weather, and each time a hilling mixture is added. Watering thoroughly and frequently helps wash the nutrients throughout the container.
Harvesting and Storing
Harvest “new” potatoes after the plant’s flower, taking care not to damage the plants. When the leaves begin to yellow and die down mature potatoes can be harvested. At this point, you can turn over the container and your harvest will tumble out!
Store potatoes in a cool (40 degrees) dark area. Potatoes exposed to light will begin to turn green and can be mildly toxic.
According to Healthline (healthline.com), an online source for physical and mental health information, “Potatoes are rich in vitamins, minerals, and antioxidants, which make them very healthy. Studies have linked potatoes and their nutrients to a variety of impressive health benefits, including improved blood sugar control, reduced heart disease risk, and higher immunity.” All good reasons to grow lots of them!
Sources and Resources
What is the best way to grow potatoes in containers? (March 2021). University of New Hampshire Cooperative Extension https://extension.unh.edu/blog/what-best-way-grow-potatoes-containers
Potatoes are Easy and Fun to Grow in Containers (March 2013). Agriculture and Natural Resources, University of California, https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=9648
Question: I’d like to plant pomegranates in a sunny side of my yard. Is this the best time of year to plant? What varieties are recommended for Denton County? Do I need two different varieties for cross-pollination? (January 22, 2021)
Answer: When pomegranates arrive in the produce department every fall, I find myself distracted by a flurry of thoughts: I need to plant pomegranates. I should have already planted pomegranates. I bet a bowl of pomegranates on my holiday table would be beautiful. I need to plant pomegranates. It’s a mad cycle, I tell you.
Lucky for you and me, this is the perfect time of year to plant pomegranates. (January-March) These delicious show-stoppers are self-pollinating, growing both male and female flowers on the same plant; however, they will bear larger fruit if cross-pollination is possible or enhanced. Studies are showing that three cultivars do best in north Texas: Al-sirin-nar, Salavatski, and Russian 18. Plant in a sunny spot on the south side of your property for best fruiting.
Plant pomegranates, and any fruit tree for that matter, with a measure of patience! It will take three to four years for the shrub to begin bearing fruit. In the interim, follow the care guidelines listed in the first linked article, below.
For the first few years that your young pomegranates are in the ground, I would recommend carefully protecting them from freeze and frost. The second link, below, lists a variety of ways to protect young plants from cold damage.
So, let’s plant now to fend off the otherwise inevitable “pomegranate regret” that plagues some of us in the produce department every fall.
Question: My nectarine tree has a gum-like disease, after heavy rain, I see lots of gum from the tree and the fruit. What is this disease called and how to treat organically? (June 12, 2020)
Answer: Thank you for contacting the Denton County Master Gardener Association with your question about your nectarine tree. We have received several inquiries lately about this issue in nectarine and peach trees. It appears your tree is suffering from the fungal pathogen Botryosphaeria dothidea, commonly known as Fungal Gummosis.
Fungal Gummosis is a vascular disease that limits the growth and production of stone fruit trees such as peaches and nectarines. Large amounts of resinous compounds exude from fungal infections at lenticels (essentially pores in the bark) or from other entry wounds on branches or tree trunks. These symptoms are brought on by physical injuries such as damage by insects or string trimmers or chemical injuries. Secondary pathogens infect the wounds leading to fungal gummosis.
Early symptoms are raised blisters near wounds or on young shoots. These lesions continue to expand under the bark clogging the tree’s vascular system resulting in limb dieback and cankers on the bark. In severe infections, the outer corky protective layer of woody stems will be very coarse with a blackish color. Severe infections ultimately result in the death of the tree.
According to the University of Florida Horticultural Sciences, disease management of fungal gummosis is very difficult. The infection can occur almost any time of the year, and, once the tree is infected it is difficult to control the infection in the inner tissues of the tree. There are no approved fungicides to treat fungal gummosis specifically. However, fungicides for treating fungal diseases in the fruit and leaves of fruit trees may help in suppressing fungal gummosis.
There are several horticultural practices for managing a fungal gummosis outbreak.
- Pruning practices:
- Avoid pruning when the tree is wet following rain or irrigation
- If the tree is stressed from lack of water or nutrition, do not prune
- Prune healthy trees first and, infected trees last
- Disinfect the pruning equipment each time after pruning infected trees with rubbing alcohol or a weak bleach solution (10% bleach, 90% water)
- Spray pruned branches and twigs with a fungicide afterward to protect the fresh wounds
- Discard pruned or downed limbs and fruit in the trash, do not compost them
- Properly prune the tree’s branches to open up the canopy for air circulation. This link from Oregon State University Extension shows how to properly prune fruit trees: https://catalog.extension.oregonstate.edu/pnw400/html
- Remove suckers from the base of the tree
- Keep weeds and grass from growing up around the base of the tree; they reduce air circulation around the trunk
- Water the root zone only using drip irrigation or a soaker hose; avoid wetting the bark, leaves or twigs of the tree especially after pruning or harvesting
- Proper fertilization will avoid excessive growth of young shoots that are particularly susceptible to fungal gummosis
- Monitor the tree daily for signs of wounds from insects, rabbits, or deer and mechanical damage from string trimmers or mowers
- Look for lesions on the bark to detect fungal gummosis to help you understand the disease severity and possible spread to other fruit trees
- Plant fruit trees in well-draining soil; correct any drainage issues if the tree is periodically in standing water
Sources and Resources
Texas A&M AgriLife Extension Plant Disease Handbook, description and photos of the diseases that can affect peach, apricot and nectarine fruit trees: https://plantdiseasehandbook.tamu.edu/food-crops/fruit-crops/peach-apricot-and-nectarine/
“Home Fruit Production – Stone Fruit” from Texas A&M AgriLife Extension, information about growing fruit trees in Texas: https://aggie-horticulture.tamu.edu/extension/homefruit/stone/stone.html
“Homeowner’s Guide to Pests of Peaches, Plums, and Pecans” from Texas A&M AgriLife Extension, information about the common insects and pests of peaches, plums, nectarines, and pecans: https://agrilifeextension.tamu.edu/library/gardening/homeowners-guide-to-pests-of-peaches-plums-and-pecans/
“Fungal Gummosis in Peach” from University of Florida IFAS Extension, information about fungal gummosis disease and management: https://edis.ifas.ufl.edu/hs1265
Question: Every year my vegetable garden gets overrun with aphids. I have tilled my soil, planted naturally repelling plants, I use a neem and soap combination spray, and I spray aphids off the plants with water, yet they always get the upper hand. This year I was considering tenting my plants with netting and releasing beneficial insects like ladybugs or katydids to help. Do you have any recommendations on places to purchase non-invasive insect species (I don’t want to release more Asian Lady Beetles!) or any other recommendations to fight off these nasty buggers? (March 27, 2020)
Answer: It sure sounds like you’re doing all the right things to try to control aphid infestation in your vegetable garden. There are few additional tips from John A. Jackman of Texas A&M AgriLife Extension that you might consider this year.
- Putting a reflective mulch such as foil paper on top of the soil below your plants can slow aphid infestation
- In early spring or early fall, when it is not blistering hot, put a fine mesh screen or fabric over your garden. Your plants will still need to be monitored regularly, preferably daily, so you will need to remove the barrier. It’s not recommended to leave barriers in place during the hot summer months because the temperature inside the barrier is warmer than outside of it so it can cause your plants to suffer from heat stress.
- High-pressure water sprays can dislodge aphids. You will need to repeat this treatment frequently.
- Use pesticides, Neem oil, and insecticidal soaps only as a last resort because these products will also kill the beneficial insects that naturally control aphids.
These tips, as well as a list of registered pesticides for use on home garden vegetables and common insect pests, can be found at this link: https://agrilifeextension.tamu.edu/library/gardening/managing-insect-and-mite-pests-in-vegetable-gardens/
Other cultural practices you may want to consider include:
- Remove any plant debris, soil residue and dispose of weeds or other unwanted plants that pop-up to get rid of the food and shelter before planting and throughout the growing season. When the growing season ends, remove these things as well so aphids will not overwinter there. Also, control of aphids is easiest after soon after they hatch from the eggs. Look for egg clusters or tight groups of eggs on the undersides of the leaves. You can gently scrape away the eggs or remove them with a blast of water. Website link: Chapter VI: Insect Management James Robinson
- Although there’s no scientific data to support this practice, some gardeners claim it is helpful to use trap plants or sacrificial plants that attract aphids to draw them away from your vegetable plants. Examples include nasturtiums and sunflowers. Be careful not to plant these too close to your vegetable plants to avoid the aphids traveling to them. In addition, consider planting plants that repel aphids amongst your vegetable plants. Plants that repel aphids include those of the allium family (garlic, chives, leeks), marigolds, or catnip, fennel, dill, and cilantro. Website link: Trap Plants For Aphids: Plants That Repel Aphids In The Garden
In discussing your issue with other Denton County Master Gardeners, we had a few questions and ideas you may want to think about that may be contributing to your aphid issue:
- Are there other plants nearby in your yard or your neighbor’s that may be attracting aphids to your vegetable garden? For example, the Cotton or Melon Aphid (Aphis gossypii Glover) food sources include begonia, catalpa, citrus, ground ivy, hydrangea, violets, and weeds as well as vegetables. Green Peach Aphid (Myzus persicae (Sulzer)) has a wide range of food sources including peaches, some flowering ornamental plants and, vegetables. Website link: Aphids in Texas Landscapes
- Are you practicing crop rotation each year? For example, not planting tomatoes or peppers which are both members of the nightshade family in the same place each season.
- Healthy vegetables can withstand some aphid damage but stressed plants are much more susceptible to insect damage. Practicing good irrigation, mulch, and fertilization habits go a long way toward growing healthy vegetables that can tolerate some insect damage and still produce for you.
- The beneficial insects you introduce will stick around only as long as there’s a food source. Once there’s no food source, they’ll move on. We think it may be better to use the row covers as you described, limit your use of pesticides including insecticidal soap to avoid killing the beneficial insects that occur naturally and practice the other cultural control methods mentioned above.
Sources and Resources
Jackman, John A. “Managing Insect and Mite Pests in Vegetable Gardens.” agrilifeextension.tamu.edu, Texas A&M AgriLife Extension, 1 Feb. 2008, agrilifeextension.tamu.edu/library/gardening/managing-insect-and-mite-pests-in-vegetable-gardens/.
Robinson, James. “Managing Insect and Mite Pests in Vegetable Gardens.” aggie-horticulture.tamu.edu, Texas A&M AgriLife Extension, 1 Jan. 2009, aggie-horticulture.tamu.edu/vegetable/guides/texas-vegetable-growers-handbook/chapter-vi-insect-management/.
Baessler, Liz. “Trap Plants For Aphids: Plants That Repel Aphids In The Garden.” gardeningknowhow.com, Gardening Know How, 4 Apr. 2018, www.gardeningknowhow.com/plant-problems/pests/insects/plants-that-repel-aphids.htm.
Jackman, John A., and Robinson, James. “Aphids in Texas Landscapes.” agrilifeextension.tamu.edu/, Texas A&M AgriLife Extension, 1 Mar. 2011, agrilifeextension.tamu.edu/library/landscaping/aphids-in-texas-landscapes/.
Question: I would like to propagate blueberries using hardwood cuttings, but I’m having trouble finding information about it. Could you help me? (January 17, 2020)
Answer: This one really took some digging (no pun intended)! Information on blueberry propagation, especially from hardwood, is not always easy to find.
Blueberries are propagated using shoots (“whips”). Whips are usually obtained from the previous season’s growth and are about 12-36 inches long. As with any propagating, make sure you select cuttings from a healthy plant. Whips are best obtained in late winter or very early spring, just before bud growth begins. Do not use shoots formed in late season. Cuttings should be from past season’s growth, mature and firm. The optimum diameter is one-quarter inch.
Cuttings are generally four inches long with four buds. The length of the cutting can be shorter if necessary. When making the cutting, avoid bruising or crushing the tissue. The best tools are sharp, clean and properly adjusted pruning shears, or a sharp, clean, knife.
Percent rooting tends to decrease progressively as cuttings get closer to flower buds. The best rooting response is seen when the distal (top) cut is made directly above the highest bud, and a slant cut is made just below the lowest bud.
As a rooting medium, a mixture of peat, perlite, and potting soil is good. Some prefer to use pure peat. It should be at least four inches deep. The medium should be soaked for three to four hours prior to planting. Cuttings are pushed vertically into the medium until only the top bud is exposed and should be about two inches apart.
Examine the soil each day for moisture level. Keep the propagation beds moist, but not soaked. Misting is also helpful. You may choose to apply a liquid fertilizer weekly. If you do that, make sure it is diluted. The cuttings may take three to four months to root and can typically stay in the propagation bed until winter. After that, they may be planted into pots or nursery beds for one year, until the next winter. Thereafter, the plants should be of sufficient size and vigor to be planted in the garden or landscape.
QUESTION: I want to plant thornless blackberry bushes this fall. My husband grew up in Washington state near a berry farm and said that blackberries grow aggressively. Are less-aggressive varieties available that will grow well in north Texas? (October 25, 2019)
ANSWER: As a child, I relished picking fresh, wild blackberries, warm from the sun! A wonderful option in North Texas, cultivated blackberries delight the senses just as well as the wild ones, with less aggressive growth. The thornless variety recommended for our area is Natchez, a semi-erect plant that requires some simple trellising in the second year. Late winter is the right time to put in root cuttings, but dormant plants can be planted anytime, although early spring is optimal. Blackberries need excellent drainage, so you may need to plant in berms of compost-amended soil.
With regard to aggressive growth, it would be best to corral these vigorous plants behind in-ground metal edging or another barrier and to pull any young shoots from undesirable locations. Make sure to keep branch tips away from the soil, as they will propagate themselves via this “layering,” as well. The cultivated varieties are not as aggressive as the wild, thankfully, but as with any hardy plant, you’ll want to keep a watch on its growth.
The articles below offer excellent recommendations.
Question: I would like to grow vegetables this fall but I don’t know where to start! What should I do with my spring vegetable garden plants? Do I need to do something to the soil to get it ready? What vegetables can I grow and when should I plant? (September 6, 2019)
Answer: Fall is a wonderful time to grow vegetables here in North Central Texas. The fall climate is much more conducive to both plants and humans! There are fewer issues with insects and damage from the hail storms we sometimes have in the spring. That being said, the steps to take to be successful with a fall vegetable garden are somewhat different than spring or summer.
Choose and prepare the garden site: You can use the same site as your spring/summer vegetable garden as long as it receives the requisite 6 – 8 hours of sun daily in the fall. If you’re planning to use a new location for your fall garden, it should be 6 feet (minimum) away from shrubs or trees to ensure full sun exposure, have good drainage and access to irrigation. There are some things you need to do to prepare the soil for the fall growing season:
- Remove all spring/summer vegetable plants that have run their course. The plant material should not be composted if it has or had any fungal or bacterial pathogens.
- Dig out, do not till under, any weeds or grass that may have grown in the garden.
- If it’s a new garden bed, shovel or turn under the soil 10” to 12”.
- Replenish the soil with 2” to 3” of organic material such as fully composted manure. If it’s a new garden bed, also add 1” to 2” coarse sand.
- Add slow-release fertilizer at the rate of 2 to 3 pounds per 100 square feet.
- Work all of these into the soil 4” to 6” with a garden fork. Tilling the soil is not recommended as it breaks down the soil structure.
- Deeply water the area for about 2 hours, then allow to dry for 2 days. Now your garden is ready to plant!
Choose your plants: As with the spring vegetable garden, grow the vegetables you and your family like to eat.
- Due to the short growing season, planting transplants rather than direct seeding is recommended except for beans, peas, beets and carrots, which do not transplant well.
- Timely planting is critical to a successful harvest. In North Central Texas, November 15 is the average first frost date. There are two ways to determine when to plant each variety:
- Calculate it: # of days to maturity + 14 days = the number of days to count backward from November 15 for your planting date
- Look it up: Use the Texas A&M AgriLife Extension Vegetable Planting Guide for North Central Texas, found at this link: https://dallas-tx.tamu.edu/files/2010/06/Vegetable-Planting-Guide.pdf
- Frost susceptible vegetables: Bean, corn cucumber, eggplant, okra, pea, pepper, squash, tomato, watermelon
- Frost tolerant vegetables: Beet, broccoli, Brussel sprout, cabbage, carrot, cauliflower, chard, collard, garlic, kale, lettuce, mustard, onion, parsley, spinach, turnip
Care for your garden: Water
- Your new transplants may need to be watered daily during September which can be just as hot as late summer. A general rule of thumb is to water new plants daily for the first 14 days after transplanting in the garden to give their root system time to establish.
- Otherwise, your garden should receive 1” to 2” of water once weekly including any rainfall.
- If the soil is dry 1” down, it’s time to water. Or, take the guesswork out altogether and purchase an inexpensive soil moisture meter.
- Although the insect pressure is lower in the fall, you’ll still need to monitor your plants daily for pests.
- If you choose to use chemical controls, choose the insecticide that is appropriate for the target insects and plants. Read and follow the label instructions carefully.
- Consider covering your plants with transparent plastic, vented during the day, or .5-ounce spunweb which doesn’t need to be vented. Spunweb covering not only will help protect against insects, it can also help filter the sun and temper the heat during September.
- Extend the growing season and protect against frost by covering with 1.5-ounce spunweb material, often referred to as “frost cloth”. Avoid letting plant covers touch the leaves by using hoops, frames or cages around your plants under the cover.
Harvest your produce: Harvesting the efforts of your hard work is also a matter of the right timing and method. This guide from Texas A&M AgriLife Extension provides a wealth of information about how and when to pick and store your vegetables: Easy Gardening, Harvesting, Handling, and Storing Vegetables, https://aggie-horticulture.tamu.edu/vegetable/files/2010/10/E-510_harvesting.pdf. A few special call-outs:
- Spinach and many greens leaves can be cut throughout the growing season to encourage resprouting, often referred to as “cut and come again”.
- To “blanch” your cauliflower heads, wrap the leaves over the head and pinch together with a clothespin or clip.
- Carrots can be stored in the soil for several weeks after they mature.
- Harvest tomatoes when they’re pink if they’re in danger of frost. They can be ripened indoors in a warm area.
Sources and Resources
Texas A&M AgriLife Extension, Denton County Master Gardener Association, Vegetable Gardening in North Texas
Question: When should I plant broccoli, cabbage, and other winter vegetables? (August 31, 2018)
Answer: A big advantage of winter gardening is that there are far fewer insects. Broccoli, cabbage, lettuce, carrots, and cauliflower can be planted any time until late September. It’s a little late for potatoes and right on the cusp for squash. List of North Texas vegetable spring and fall planting dates.
Question: My tomato plant has spots on the leaves. What is wrong with it? Do I need to spray it?
Answer: There are so many tomato conditions and diseases that A&M wrote a whole section of their horticulture website to help you solve it. It is divided into problems with fruit, leaf, stem, root, and insects. Cleverly enough, they called it “Tomato Problem Solver.” It has great pictures so that you can identify your problem, and it will also tell you what to do about it.
Question. Why are tomatoes so fussy in our area? What varieties will do well here? (March 23, 2018)
Answer: That is one big question, and we should have a tomato class to explain it all! But we will try to break it down. First, tomatoes cannot pollinate well when daytime temperatures are above 90 or nighttime below 70. Now think about when our temperatures start doing that. Early, right? So, you must plant them very early to get the best harvest, and then prepare to cover them if we have a late frost. Because many older standby varieties are no longer available.
Be aware that some stores selling tomato plants may have varieties that are challenging to grow here in North Texas. A general guideline is to select small to medium-sized types rather than the very large ones that do better further north. Neil Sperry, in a recent Facebook post, suggested trying Celebrity, Porter, Roma, Cherry, Sweet 100 or Yellow Pear.
Secondly, some tomato varieties produce again in the fall and some do not. When you buy a transplant, the label should indicate whether it is “determinate” or “indeterminate”. Determinate plants have a big, showy production for a couple of weeks, and then they are done. These plants are bushier and don’t get as tall, and if you want to make tomato sauce, you would look for a determinate plant. But indeterminate plants continue to grow taller and taller. They will stop producing when it gets hot but will resume production when temperatures moderate in the fall.
Thirdly, the variety you plant may or may not be adapted to our extreme heat. Unfortunately, there are not many seed companies left, and they cater to the big tomato producing areas on the East and West coasts. So many of the heat tolerant varieties you relied on in the past are simply not available anymore. Dr. Jerry Parsons discussed this in the following article.
How about heirlooms, you ask. Sure, go for it if you want. Just know in advance that their production is light, and you will most likely fight insects and diseases. There is an old saying here that heirlooms are the best way to get a $2.99 tomato for a few hundred dollars. But they do taste wonderful, and it might be worth it to you.
Question: I’m bewildered by the huge number of vegetables available in stores and online. Is there a list of what does well here? And how do I know when to plant what?
Answer: Here’s a great resource for when to plant, how deep, and how far apart. Vegetable Planting Guide. And here are two resources for recommended cultivars for North Texas: Recommended Vegetable Varieties and Vegetable Variety Selector (enter your county and recommended cultivars appear as a list).
Question: I’m a new gardener and would like to start a vegetable garden this year. Where do I start?
Answer: Start with the one page “Beginner’s Guide to Vegetable Gardening” on the vegetable page of our website. In five easy steps, you will find soil, sun and water requirements as well as links to specific varieties that work well in Denton County. If you are working with existing soil in a row or raised bed, getting a soil test to see what minerals and nutrients are needed is a good way to start your preparation for planting. You can get your soil tested through http://soiltesting.tamu.edu/. Their website explains how to collect a soil sample and complete the submission forms. Additional information is available from Introduction to Vegetable Gardening presentation and once you get started, there is extensive information here: https://dcmga.com/north-texas-gardening/vegetable-gardening/
Question: Can I save vegetable seeds for next year?
Answer: This is a fairly complicated question. Hybrid vegetable seeds will not reproduce as you might expect. If you are determined to save seeds, designate a few plants to allow to seed and take precautions to be certain they are not cross-pollinated. See this article about hybrid varieties and saving seed for a full discussion of hybrid seeds, which seeds you can save, and how to prepare them.
Question: Will my spring tomatoes produce more fruit in the fall?
Answer: It is possible if you have indeterminate tomatoes (they continue to grow taller throughout the season) that are still healthy. Most of the determinates will shrivel and die during the summer.
Question: Can I locate my vegetable garden over the septic leach field?
Answer: It is possible but probably not advisable. This is a quote from the Virginia Cooperative Extension Service: “Sometimes the ideal place to put a vegetable garden seems to be over the leach field, raising the question of bacterial and viral contamination from the effluent. Soils vary a great deal in their ability to filter viruses and bacteria. Clay soils work best, eliminating bacteria within a few inches of the drain trenches, but sandy soils may allow bacterial movement for several feet. A properly operating system will not contaminate the soil with disease-causing organisms, but it is very difficult to determine if a field is operating just as it should. If at all possible, use your septic drain field for ornamentals and plant your vegetables elsewhere. If you must plant vegetables, take the following precautions. Do not plant root crops over drain lines. Leafy vegetables could be contaminated by rain splashing soil onto the plant, so either mulch them to eliminate splashing or don’t grow them. Fruiting crops are probably safe; train any vining ones such as cucumbers or tomatoes onto a support so that the fruit is off the ground. Thoroughly wash any produce from the garden before eating it. Do not construct raised beds over the field; they might inhibit evaporation of moisture.”
Question: What is wrong with my grapes?
Answer: Under the microscope, we found larva that looked like this picture. Your grapes have grape berry moth. For control, see this berry moths information article.
Question: What kind of black-eyed peas do well in Denton County?
Answer: Blackeye #5, Colossus, Mississippi Silver, Pink Eye purple hull, Texas Pinkeye, or Zipper Cream. For other vegetable and fruit recommendations, see the Vegetable Variety Selector.
Question: What variety of peach and pecan trees do well here?
Answer: PEACHES are not the easiest fruit to grow in Denton County, but these are the recommended varieties: Springgold, Bicentennial, Sentinel, Harvester, Ranger, Redglobe, Fire Prince, and many others. For more information, see the Home Fruit Production — Peaches page.
It is very difficult to grow peaches organically. A well-timed spray schedule will increase your chances of getting good fruit. This article will give instructions and timing.
PECANS: Sioux, Choctaw, Wichita, Cheyenne, Pawnee, Forkert, Cape Fear, Kiowa, Caddo. For more information regarding growing pecan trees, including pruning, fertilizing, pests and diseases, go to the Aggie Horticulture Home Fruits – Pecans page.
Question: My children gave me an azalea plant last Mother’s Day. I loved it! Such lovely flowers and it was supposed to like some shade, which I have in abundance. Unfortunately, although it bloomed for a while then it stopped and just looked pitiful. It may be dead. I love azaleas and want to try again. Is there a secret about how to keep azaleas healthy? (February 11, 2022)
Answer: It is easy to love the beautiful blooms of azalea plants and a drive through the Tyler “Azalea and Spring Flower Trails” is inspiring. However, your experience trying to keep your plant alive in North Central Texas is not unusual. Azaleas along with some other attractive flowering shrubs like camellias, gardenias and rhododendrons want something that is hard to come by in our native North Texas soil—acid.
Remember back in school chemistry class, teachers talked about the pH scale. It measures acidity and runs from 0 (pure acid) to 14 (alkaline). Plants grow best when the soil pH matches their needs. Soil that is too acidic or too alkaline results in a sickly or non-productive plant. Azaleas like their surrounding soil to be slightly moist with a pH of around 5.5 (a pH of 7 is considered neutral). The typical soil pH in North Texas runs from 7.5 to 8.5. So, what can you do to help your azalea plant thrive?
Selecting a variety: There are hundreds of varieties of azaleas that grow around the world. Read the plant label to match the plant’s eventual size, flower color and cold hardiness with your growing conditions.
Location: traditional or older varieties of azaleas prefer partial shade, while the newer varieties like Encore, can tolerate full sun. So, check the plant label to find out which variety you are selecting. The University of Missouri Extension Services recommends, “A site sloping to the north or east is usually best, because it is protected from drying south and west winds. Here they are less subjected to rapid temperature changes in late fall or early spring.” Finally, avoid planting azaleas near trees that have shallow root systems which will complete with your shrub for water and nutrients. These include maples, willows, cottonwoods, pin oaks and ash trees.
Next, and most important, is soil preparation. You can purchase soil specifically for growing azaleas and other acid-loving plants. Or you can add about 50% well-composted, organic material to your existing soil. Adding pine bark or pine-needle mulch, sulfur or iron sulfite and using an acidic fertilizer helps lower soil pH. It is essential that your soil drains well. If you need to check the soil drainage, here’s a simple test you can do: “Improving Landscape Soils” https://aggie-horticulture.tamu.edu/earthkind/files/2010/10/soilimprovement.pdf.
Caring for your azalea: Add a 3-inch layer of mulch around your plant to moderate soil temperature and preserve moisture. The mulch should be place around, but not touching, the base of the shrub. Regular watering, especially when the weather gets hot, is essential. “To determine when to water, pull back a small area of mulch near the base of the plant and check the moisture level of the root ball and surrounding soil. If the top few inches of soil feels dry, wet the soil deeply, to at least a depth of 6 to 8 inches.” (Clemson University)
Because you created nutrient-rich soil before planting, your azalea usually does not require additional fertilizer in the first year. In subsequent years, a light application of fertilizer in the spring is suggested. The acid fertilizer may be added on top of the soil around the plant as it has shallow roots that can access that nutrient easily.
You may choose to prune your azalea to remove dead branches or thin out areas blocking sunlight from the interior. Occasionally azaleas are bothered by spider mites and lacebugs or diseases such as blight or leaf spots. The Texas Plant Disease Guide for azaleas list common disease problems and treatments: (https://plantdiseasehandbook.tamu.edu/landscaping/shrubs/azalea/).
Question: I was given a potted chrysanthemum as a gift in early December. Can I transplant it into my flower bed? Will it survive the winter? (December 10, 2021)
Answer: The beautiful chrysanthemums we see in garden centers and florist shops during the fall season are generally not hardy enough to survive freezing temperatures in the winter. This is because the plant will not have had time to develop a strong enough root system to survive winter if planted in the fall. The best option is to pinch it back and bring it inside to the garage or house. Water it when the soil dries out.
Garden chrysanthemums , on the other hand, are planted in the spring and have the best chance for overwintering. Garden chrysanthemums bloom in the late summer and fall and come in many colors – white, yellow, pink, purple, bronze, red, and many cultivars – singles, anemones, decoratives, pompons, spoons, spiders and standards.
Look for garden chrysanthemums in garden centers and plant nurseries in the spring. Here are some tips for planting and caring for them:
- Plant in well-drained soil with full sunlight (6 to 8 hours a day).
- Space them at least 18 inches or up to 36 inches apart to give them plenty of air circulation to mitigate fungal infections and provide enough space for them to develop a full mounded shape.
- Layer 2 inches of mulch over the root zone leaving a gap between the mulch and the stem(s).
- Fertilize monthly from the time of planting until July when flower buds form. Use a complete fertilizer with an N-P-K ratio of 6-2-4 or 4-2-3 or a water soluble fertilizer with an N-P-K ratio of 20-20-20.
- Each month, from May to July, pinch back new shoots to 3 inches to 4 inches to encourage a compact round shape and more flowers. Stop pinching back when you see flower buds, usually in July.
- Water deeply 4 inches to 6 inches when the soil is dry, in the morning to allow the foliage to dry.
- Check and treat for aphids and spotted mites with a labeled product, carefully reading and following the instructions.
- To overwinter, cut-off the dead tops and cover with 3 inches to 4 inches of mulch . Uncover them in spring as soon as they start to show new growth. Divide the plants when they reach 4 inches in height.
Learn more about garden chrysanthemums from these articles at the below links:
Give a garden chrysanthemums a try in your landscape next spring. You’ll be rewarded with flowers in the fall when most other ornamentals have stopped flowering.
Question: When should I divide the iris growing in my garden? Should I cut back the leaves, too? (October 1, 2021)
Answer: Iris is a beautiful choice for North Texas gardens. They’re very tough, drought-tolerant, and best of all, beautiful. Here’s a list of tips for maintaining a healthy iris.
Iris should be thinned every 2 to 3 years. The larger rhizomes will start to push above the ground when the plants become overcrowded. September and October are the best months to divide and replant iris.
Plan to have these materials on hand: gloves, garden/digging fork, spade, hand pruners, bucket, sanitizing wipes or a spray bottle with a weak solution of water and bleach (1 part bleach to 9 parts water), and a knife to cut up the rhizomes (a Hori Hori or Japanese digging knife works well).
Steps to Dividing Iris
- Using hand pruners, cut the leaves back to ⅓ of their full height. Note: Do not cut back the leaves of established iris you do not plan to divide. The foliage is needed to build up food reserves for spring flowering.
- Dig under the clump of rhizomes with the garden/digging fork, and lift the whole clump out at once. Set aside the clump for separation.
- Select only firm, whitish-colored rhizomes to divide. Discard any rhizomes that are dark-colored or soft.
- Cut the healthy rhizomes into sections containing 1 to 3 buds, at least one fan of leaves, and a few inches of well-developed roots. Drop the divided rhizomes into a bucket. Clean and disinfect the blades of the pruner or knife with sanitizing wipes or the weak bleach solution before cutting more rhizomes or leaves if you cut into diseased rhizomes (dark, soft).
- Discard any unhealthy plants or rhizomes in the trash. Do not compost them.
Replanting Divided Iris Rhizomes
Plant iris in a sunny location with well-drained soil. If poorly draining soil is a problem, plant them in a raised bed. The rhizomes need the light and heat from the sun to set blooms next spring. Planted the rhizomes very shallow, no more than ¼ inch below the surface of the soil.
Water thoroughly after planting. Usually, supplemental watering is not needed (remember they rot easily) unless there is a prolonged period of no rainfall.
A soil analysis is the best way to know if fertilizer is needed. Use this link to obtain the Urban and Homeowner soil test form, which includes instructions for collecting samples, payment, and mailing: http://soiltesting.tamu.edu/files/urbansoil.pdf. The forms and sample bags are also available at the Denton County office of Texas A&M AgriLife Extension Service. Some gardeners work a complete fertilizer (5-10-5) or bone meal into the top few inches of the soil after planting.
Friends and neighbors will enjoy iris, too, so please be sure to share any extra healthy rhizomes you have. Here’s a link from Texas A&M AgriLife Extension, Aggie Horticulture, about growing iris: https://aggie-horticulture.tamu.edu/archives/parsons/flowers/iris.html.
Question: Howdy, I’m asking about my Lord Baltimore hibiscus. It’s overall healthy and blooming well. But this season, I’ve have had numerous brown leaf spots then eventually leaf yellows and spots turn darker. Now I’m noticing that some flower buds are yellowing and dying out before bloom. It also has banded-wing whitefles with eggs underneath a lot of leaves as well but that’s pretty normal. Not sure if the two are related though. I have treated a couple of times with Neem oil and once with the Bayer Advanced Fungicide/Miticide spray but it hasn’t slowed it down yet. Any other advice you might give? (July 9, 2020)
Answer: Lord Baltimore hibiscus (Hibiscus moscheutos), also known as Rose Mallow, is a shrub with huge, beautiful red flowers. It is native to wet, marshy areas in the southeastern United States. They bloom from August to October with multiple flowers per plant, each flower lasting only 1 day.
I suspect your plant may be suffering from several issues:
Thrips are a tiny, slender insect with fringed wings. They are likely eating on and damaging the buds at a young age. To control thrips, apply a contact insecticide every 7 to 14 days, thoroughly covering the buds, shoot tips, and any other areas showing damage. Organic options include insecticides with active ingredients azadirachtin, insecticidal soaps, horticultural oil, neem oil, and pyrethrins. Spinosad is more effective than these. Mix it with horticultural oil to increase its persistence within the plant tissue. This link from the University of California provides more information on thrips: http://ipm.ucanr.edu/PMG/PESTNOTES/pn7429.html
Hibiscus moscheutos requires wet to consistently moist soil to thrive. Your plant may be suffering from leaf scorch if the soil is drying out between waterings. Inadequate moisture can result in scorch symptoms on foliage, stunting, leaf yellowing, leaf drop, and flower bud death before bloom.
You could also have a fungal issue. In all cases of plant diseases, practicing good sanitation is important to avoid spread:
- Pick up and discard any plant debris and remove infected leaves, do not compost these.
- Clean tools used to prune diseased plants with a weak solution of bleach, rubbing alcohol, or a disinfectant.
- Don’t let mulch touch the stem to prevent Southern stem blight.
Treat with a fungicide at the first sign of the disease following the label directions for the first and subsequent applications. Please carefully read the label to be sure it’s suitable for hardy hibiscus, and carefully follow the application directions and safety precautions. This factsheet from the University of Florida lists fungicides that are suitable for ornamental plants: http://edis.ifas.ufl.edu/pdffiles/pg/pg08900.pdf
This website from North Carolina University has more info about Hibiscus moscheutos: https://plants.ces.ncsu.edu/plants/hibiscus-moscheutos/. This website from Clemson University has more general information about hibiscus: https://hgic.clemson.edu/factsheet/hibiscus/
Question: The leaves on my favorite rose of sharon started browning last week, and now, the plant looks nearly dead. I’ve included a photo. What could have happened? If I can’t save it, can I re-plant a new rose of sharon in its place? (June 26, 2020)
Answer: What a heartbreak to see such a beauty fail so rapidly. Diagnosing disease from photos alone is a challenge; however, the most likely culprit is cotton root rot (Phymatortrichum omnivorum). Rose of sharon is highly susceptible the fungus, which is active during this time of year and advanced by overwatering. Is it possible that you could be overwatering in an attempt to save the shrub? Or could there be an irrigation/pool leak in the area?
Before giving up on your plant, first correct any water or drainage issues you may have. Run each zone of your irrigation system for a minute or two. Put on your raincoat and wellies and look closely at each sprinkler head and your entire drip line. Sometimes water will spew like a geyser; other times, you’ll see bubbling water at the base of sprinkler heads or a flowing stream from your drip lines. If you see leaks or misdirected sprays, correct them. Do this check every month you use irrigation.
Next, get into the habit of checking soil moisture before running irrigation. Use a screwdriver to probe the soil to a depth of 6-8 inches. If you’re able to probe to that depth, moisture is sufficient and no watering is necessary. Alternatively, invest in an inexpensive (<$5) soil moisture meter, and spot-check your landscape before watering (to the same 6-inch depth).
If you’re not able or inclined to manually check the soil, or if you travel, then consider upgrading to a smart controller. It uses your local weather station’s current evapotranspiration (ET) readings to calculate irrigation. (ET refers to evaporation that comes from the soil itself as well as from the plants’ leaves.) The controller doubles as a rain/freeze sensor, shutting off when temperatures drop below freezing or when local rain exceeds a set threshold. Once installed and linked to your WiFi, these smart controllers can be programmed and adjusted from the controller itself, or from your smartphone, tablet or computer.
The following document describes how to possibly save ornamental plants suffering from cotton root rot by using ammonium sulphate to acidify the soil, creating an unfavorable growing condition for the fungus. This option is a last resort, but it is inexpensive and fairly easy, so it might be worth a try. The downside is that you’ll have to continue acidifying the soil every year, which may become tiresome. In short, prune the shrub back. Build a ridge of soil about four-inches high around the tree’s drip line. The circumference of the ridge-line should be equal to the diameter of the crown/top of the tree. Work into this soil one pound of ammonium sulphate for every 100 square feet of area within the ridge. Fill the ridge with water to a depth of four inches. Repeat this treatment five to ten days later. Limit treatment to twice per season. Refer to the section at the end of the article entitled “Fertilizer Applications.”
If your shrub dies completely, and you wish to replant another rose of sharon, do not replant it in the same location, since the fungus remains active in the soil for years. Instead, plant it in a sun/part-sun location where drainage is excellent. These beauties like moist soil, but not standing water. In its place, plant a flowering shrub resistant to cotton root rot (see link below).
Question: I have over 60 daylilies that have been in their current location five years, and until this year, they have had tall scapes and lush foliage. This year, the leaves are turning yellow and the scapes are very short. What is happening? (May 22, 2020)
Answer: Daylilies often seem so carefree and hardy that their health is easy to take for granted. In trying to find clues to your daylilies’ stress, you will want to check for insects and pests as detailed below, but first let’s consider their overall environment and next their specific physical condition.
It seems that your daylilies have been performing satisfactorily for five years where they are planted now, but that their decline has been sudden this year. Here are a few questions about possible changes in their general environment:
- Could your daylilies have been exposed to herbicide applications like “Weed and Feed” or any other herbicide through spray, run-off or drift?
- Has shade been encroaching on their beds over the years? Daylilies need at least 6 hours of sun daily for best blooming, though they will tolerate filtered light. This is probably not responsible for a sudden decline but can cause spindly growth and lack of blooms.
- Have there been any interruptions in the bed’s drainage (construction or something else)? The beds should be able to hold moisture but also be well-drained.
- Overwatering, overhead watering, and poor drainage can be the source of bacterial root rot and fungal disease. Overcrowding and poor air circulation may be a cause of disease and insect infestation. For this reason, daylilies should be divided every three to five years, preferably in the early fall.
Daylilies can do well over a relatively wide soil pH range and adjustment of pH need only be considered if the plants appear to be doing poorly, which yours are. I advise that you submit a soil sample for testing to Texas A&M soil lab. This will give you information for the pH and nutrient characteristics of your soil, as well as recommendation for adjustment, if it is necessary. The link to the Texas A&M University Soil Testing Lab is below.
As soon as possible, you can check drainage and possible overcrowding. You need to inspect the daylilies for signs of disease and pests, using the Clemson Cooperative Extension article linked below as your guide. It gives descriptions of common diseases (daylily rust, leaf streak, root rot, etc.) and pests that afflict daylilies and how to control them. We have had a very warm winter, so the surviving spider mite population, for instance, will be large and hungry. A serious case of rust or infestation of spider mites could be the immediate cause of your problems, but some environmental or cultural adjustments may also be in order to correct underlying conditions.
However, for a definite diagnosis, you may also submit a sample to the Texas A&M Plant Disease Diagnostic Lab (about $35).
TAMU Plant Disease Diagnostic Lab: https://plantclinic.tamu.edu/
Texas A&M soil testing lab (A basic soil test is $12; use the Urban/Homeowner submittal form.): http://soiltesting.tamu.edu/
Question: I live in Oak Point and was wondering if I can use a pre-emergence product on a rose bed where mature roses have been growing for several years. I wondered if a pre-emergence would help control weeds or would damage the roses. (February 21, 2020)
Answer: Weed control in ornamental beds is a constant chore. There are several methods for weed management including mechanical removal, mulching or sheet mulching and, chemical control. Let’s walk through the pros and cons of each in managing the weeds in your mature rose bed. According to John F. Karlik of the University of California Agriculture & Natural Resources, in most home rose garden beds, mulches supplemented with regular hand weeding should provide enough weed control.
Mechanical Weed Removal
Roses are shallow-rooted plants so care needs to be taken when mechanically removing weeds. Using hand tools is best rather than hoes to avoid damaging the roses’ roots. My favorite is a Hori-Hori garden knife. Remove the weeds when they are young before they go to seed. Attempt to remove the entire weed plant including the roots.
Mulching or Sheet Mulching
John Karlik recommends mulching with 2 to 4 inches of organic material such as wood chips to reduce annual weeds and make hand-weeding easier in the rose bed. I have personally found sheet mulching to be the most effective method for reducing weeds in my ornamental beds.
Sheet mulching also referred to as sheet composting or lasagna composting is an excellent way to control broadleaf and grassy weeds in your ornamental beds while improving the soil at the same time! Here are the steps I take every spring, usually after the last frost, to prepare my ornamental beds for the growing season:
- Start by mechanically removing any weeds or grass in the beds.
- Pull back any existing mulch and cover the soil with overlapping layers of cardboard or several layers of newspaper. The carbon in these materials smothers the broadleaf and grassy weeds.
- Thoroughly wet the cardboard or newspaper covering and add a layer of fully composted material to add nitrogen. Composted manure is a good choice.
- Top that layer with 2” to 4” of mulch such as wood chips.
- These layers will decompose over time improving the condition of your soil by adding microbes and nutrients to the soil that your plants need to be healthy.
Woven landscape fabric can also be placed over the soil and then covered with mulch to provide weed control. This material, of course, does not improve the soil as sheet mulching does.
There are preemergence herbicides that can be used around roses before weeds emerge. John Karlik recommends preemergence herbicides with the active ingredient oryzalin or pendimethalin which have been effective in field trials and did not injure the rose plants. Preemergence must be applied when the soil temperatures are below 55 degrees and air temperature is consistently below 70 degrees. In North Texas, this is typically mid-to-late March.
To control grassy weeds that have already emerged, John Karlik recommends
postemergence herbicides with the active ingredients fluazifop-p-butyl or clethodim which were also effective in field trials and did not injure the rose plants.
Mr. Karlik also warns against using any broadleaf postemergence herbicides around roses such as 2,4-D, triclopyr, and dicamba as roses are sensitive to those chemicals. In addition, non-selective herbicides such as glyphosate should not be used near roses.
Always check the labels of each herbicide before using for labeled bedding plants, susceptible weeds and any precautions that should be observed.
Combine All 3 Methods for Success
You will likely need to combine all three methods – mechanical removal, mulching, and chemical control – to completely control the weeds in your rose beds. The combination of mulching/sheet mulching and using preemergence herbicides can make a real reduction in the amount of hand weeding needed during the growing season.
Sources and Resources
Karlik, John F. “Roses: Cultural Practices and Weed Control.” ipm.ucanr.edu, University of California Agriculture & Natural Resources, 1 Jul. 2019, ipm.ucanr.edu/PMG/PESTNOTES/pn7465.html.
Trinklein, David. “Weed Control in Ornamental Beds.”ipm.missouri.edu, University of Missouri, 9 Jun. 2016, ipm.missouri.edu/MEG/2016/6/weed_control/.
“Sheet mulching — aka lasagna composting — builds soil, saves time.” oregonstate.edu, Oregon State University Extension Service, 1 Feb. 2004, extension.oregonstate.edu/gardening/techniques/sheet-mulching-aka-lasagna-composting-builds-soil-saves-time.
Question: I have noticed scale on my Crape Myrtles. How do I treat this? (August 20, 2021)
Answer: Thank you for contacting the Denton County Master Gardener Help Desk with your question about how to treat scale on your crape myrtle trees. Your trees are likely infected with a crape myrtle bark scale (CBMS, Acanthococcus Lagerstroemia).
What It Is
Crape myrtle bark scale is a sap-feeding insect that lives on the bark of some plants, especially crape myrtles (Lagerstroemia species). They secrete a sugary substance called honeydew that results in a black mold on the branches and trunk. Although the scale will not kill the plant it can result in stunted growth and reduced flowering and the black mold is certainly unsightly. Also, honeydew attracts ants (Merchant).
- To remove the black mold wash the trunk and branches with a weak solution of water and dish soap with a large brush like the type used to wash a car (Laminack).
- While the tree is dormant during the winter spray the trunk and branches with dormant oil to smother overwintering scale insects (Laminack). Dormant oil is highly refined mineral oil and is eco-friendly.
- To get ahead of the pests next year apply a drench type systemic pesticide in mid-March. The systemic pesticide should contain imidacloprid or dinotefuran (Williams).
- If you continue to have issues during the spring and summer the trees should be treated with a contact insecticide spray that contains the active ingredient Bifenthrin. A second treatment may need to be applied 2 weeks later (Williams).
Here are a few tips for healthy and beautifully blooming crape myrtles next season:
Planting (Collin County Master Gardeners)
- Choose a variety of crape myrtle that will grow to a suitable width and height for the location.
- Plant your trees in well-drained soil with full sun exposure, at least 6 hours daily.
- Dig a hole two times wider than the root ball. The tree’s root crown should be no deeper than the depth it was in the container or slightly higher than the surrounding soil. Backfill with the same soil that was removed from the hole; do not add amendments such as fertilizer or compost.
- Water thoroughly after planting. Add a 3” to 5” layer of mulch in the root zone leaving a 2” to 4” gap between the mulch and the tree’s trunk.
Fertilizing (Dr. Jerry Parsons)
- In early spring apply a complete slow-release fertilizer (N, P, K 19-5-9) at the rate of 2 pounds per 1000 feet of the branch spread of the tree.
- Make a second application in late fall.
Watering (Collin County Master Gardeners)
- Newly planted trees should be deeply watered 2 inches once a week in the absence of rain for the first couple of months.
- Crape myrtles are drought tolerant. Established trees should be deeply watered 2 inches once a month. The weekly light watering applied to your lawn grass is not adequate.
Pruning (Collin County Master Gardeners)
- Be selective when pruning to remove only broken branches or crowded growth in late winter or early spring.
- Pruning encourages new growth so avoid pruning in early fall before the first frost which can result in freeze damage to the new growth.
- Remove suckers that grow at the base of the tree at any time.
- Remove spent blooms to encourage reblooming.
Sources and Resources
Laminack, Janet. “Crape Myrtle Bark Scale.” DCMGA.com, Denton County Master Gardener Association, 21 Dec. 2016, youtu.be/lbFPSWEJhvc.
Merchant, Mike. “How to Treat Your Crape Myrtle for Bark Scale.” citybugs.tamu.edu, Texas A&M AgriLife Extension, Insects in the City, 28 Aug. 2018, citybugs.tamu.edu/2018/08/28/how-to-treat-your-crapemyrtle-for-bark-scale/
Williams, Rob. “Crape Myrtle Bark Scale Study Reveals Tree Treatments to Fight Pest.” https://ipm.tamu.edu/,Texas A&M AgriLife Extension, Texas IPM Program, 10 Mar. 2017, ipm.tamu.edu/2017/03/crape-myrtle-bark-scale-study-reveals-tree-treatments-to-fight-pest/.
Parsons, Ph.D., Jerry. “Crape myrtle -The Perfect Texas Landscape Plant.” https://bexar-tx.tamu.edu/, Texas A&M AgriLife Extension, Extension Education in Bexar County, 4 Sep. 2005, bexar-tx.tamu.edu/homehort/archives-of-weekly-articles-davids-plant-of-the-week/crapemyrtle-the-perfect-texas-landscape-plant/.
Question: My bearded irises didn’t bloom very well this year, so I guess they need to be divided. Could you give step-by-step instructions for dividing and replanting? (August 30, 2019)
Answer: With rather showy blooms, the bearded iris might appear to be a garden diva, needing more attention than a pop star in decline. Granted, digging and dividing every three to five years demands a toll, but these drought-tolerant beauties offer a return much greater than the investment. Read on for step-by-step instructions and links for further research.
Timing and frequency of division
* Divide every three to five years or when blooming diminishes.
* In North Texas, divide in August or September. Blooming is complete, but there’s still time to establish a new root system before winter.
* Do not dig your irises in rain-saturated soil, which will become overly compacted if you do. Wait a few days after heavy rain.
* Before digging, cut leaves down by one-third of full height.
* Use spading fork to lift the entire clump. If you use a shovel instead, avoid getting too close to the clump so you don’t damage rhizomes or roots. Shake soil off the clump or use a strong jet of water to rinse off the soil.
Dealing with old or diseased rhizomes
* Remove rhizomes with borer damage and those that are soft or appear diseased. Put in regular garbage. Sterilize any tools that came into contact with the diseased plants in a 10% bleach solution.
* Remove aging rhizomes that look like leather or cork; usually, these old growths will not produce again. Do not compost iris bulbs.
Separating healthy rhizomes
* Separate the remaining, newer rhizomes. Each divided clump must have a “fan” of four to five leaves, at least a few inches of rhizome, and some healthy, white roots. Label the fans with permanent marker to more easily identify the varieties later.
* Place these newly separated clumps into a bucket with a 10% bleach solution for a few minutes while you amend the existing planting hole.
Amending the soil and fertilization schedule
*Amend the existing site with compost, mixing well. Some recommend using superphosphate in the amendments, but north Texas soil is generally high in phosphorous, so it is probably unnecessary. Withhold fertilizer until early spring, then use a lower nitrogen product, 5-10-5 or 6-10-10. Repeat fertilization after blooming and in late fall.
* To plant, form a mound of soil in the planting hole so that the top of the mound is about one inch below the top of the bed. Place the rhizomes on the mound with the roots extending down the sides and into the hole. Read the links below to learn how the angle of the fans and placement of the rhizomes impact the growth pattern and the overall design.
* Backfill carefully, covering the roots first and compacting the soil into place. You may need to hold the rhizome while backfilling so it remains at nearly ground level. Continue backfilling until the soil covers all the roots and one-half of the rhizome. Compact the soil gently, but firmly.
* Thoroughly water-in the transplants. Keep moist for the first two weeks as the plant establishes its root system, but do not allow standing water. Once established, irises need little water. If overwatered, the rhizomes will rot.
Mulching (Don’t do it!)
* Do not mulch the exposed rhizome. Covering the fleshy stem encourages rot and disease.
QUESTION: I love to see my neighbor’s daffodils bloom in late winter, but then I kick myself for not planting my own bulbs soon enough. When should I plant spring-flowering bulbs, and what low maintenance choices do you recommend? (August 23, 2019)
Answer: By late winter, many of us yearn for the first glimpse of a bright daffodil. Bulbs require planning and patience, but thankfully, you’re not too late this year. Since it’s too hot to garden at the moment, plan your design and order desired bulbs in the next month or so for the best selection.
The broad term “bulb” describes plants that store most or part of their lifecycle within an underground, fleshy structure. Bulbs planted in the fall spend months growing the root structure necessary to sustain the showy flowers that cheer us in the doldrums of winter. Once blooming finishes, the leaves continue photosynthesis, storing nutrients in the bulb for next year’s blooms. As the leaves yellow and fade, we know it’s time to prune and await next year’s showing.
Most gardeners prefer perennial bulbs, which respond to our climate by continuing to bloom for a number of years before needing to be divided and shared. In north Texas, spring-blooming examples include daffodil/narcissus, grape hyacinth, and allium, among others. In the ever popular “tulip” category, look for “species tulips” that naturalize in north Texas, as opposed to the more widely known hybrid tulips that demand higher maintenance.
Plant bulbs when soil temperatures reach about 55 degrees. Planting too soon triggers leaf growth before a root system develops. Underground bulbs withstand freezing weather, but premature leaf growth succumbs to the same temperatures. Planting a little late is better than planting too early or, worse yet, saving the bulbs until the following year. If you order bulbs early, store them in a refrigerator away from any methane-producing fruits or vegetables until planting; do not allow them to freeze.
Question: My flower beds look straggly and worn from summer’s heat. What shrubs and flowering plants are safe to “clean up” now and what should I leave for later? (July 26, 2019)
Answer: Mid-summer deadheading and light shearing revives flowering plants to generate a late summer flush of new growth. Even a light pruning of berry canes or removal of dead branches in woody ornamentals is helpful. The keyword is “light”; heavy pruning this time of year is not recommended.
First, let’s define terms. Deadheading entails the removal of spent flower heads and stems down to the nearest leaves; don’t just pull off the petals. Plants commonly deadheaded include daylilies, coneflowers and roses. Light shearing involves the mass removal of the top few inches of the plant, or down to the bulk of the foliage. This trimming is best for plants with small flowers closely spaced, like salvia Greggii, coreopsis and dianthus. Pinching back is the hand-removal of branch tips just above a leaf joint. This simple step encourages the emergence of side shoots, making a bushier plant. Coleus, marigolds and basil benefit from pinching back.
- Shrubs, annuals and perennials that bloom before mid-June are considered “spring flowering,” and they should have already been pruned. If you missed trimming them, just wait until next spring. If you prune them now, you may remove foliage necessary for next year’s blooms.
- Prune, deadhead, lightly shear and pinch back plants that began flowering this summer (after mid-June).
- Roses shouldn’t be pruned now, but definitely deadhead spent blooms.
- Avoid removing emerging buds.
- Never trim drought-stressed plants; make sure to prune after rainfall or irrigation.
- Wear garden gloves and watch out for paper wasps, asps and other pests nesting in your plants.
- Clean pruning tools between cuts on diseased plants. Use 70% rubbing alcohol. Don’t use bleach.
When to prune flowering shrubs and which to avoid pruning in summer: https://aggie-horticulture.tamu.edu
Details on pinching back: https://ucanr.edu
Question: What shrubs can I plant to attract butterflies in Denton County? (October 5, 2018)
Answer: Fall is a good time of year to plant shrubs, so this is a timely question. The survival rate to adulthood is only about 5 in 500 butterfly eggs. There are many reasons for this, but a big one is spraying for insects. If you are serious about butterfly gardening, you should forego pesticides.
Abelia, agarita, barberry, spirea, Texas sage, sumac, and Texas honeysuckle are all good shrubs for nectar. But of course, you must also plant host plants for the females to lay their eggs and for the larvae to eat. One of our Texas Master Naturalist friends compiled a list of host plants and nectar sources for 21 butterflies common in our area. Don’t you love when someone has done the work for you? It is a very helpful article.
For a complete list of native and adapted butterfly plants, go to Texas Smartscape. If you scroll down to “wildlife value,” one of the options is “butterflies.” You can input as many parameters as desired.
Question: My plants look fried. I’m not at all sure I’m watering enough for this heat. Can you give me some guidance? (July 20, 2018)
Answer: North Texas’ often extremely hot summers can be hard on many plants. Knowing when and how much to irrigate grass, trees, vegetable garden, and flower beds can help. Don’t forget to add mulch to retain moisture and moderate temperature of the soil. AgriLife offers this advice on the most effective ways to add supplemental water.
Some plants are better able to take the heat than others. After our last terrible drought year in 2011, we surveyed our members to find out what thrived, what survived, and what died. You might want to look at that list for future planting.
Question: When should I fertilize my roses?
Answer: Roses should be fertilized around the middle of February—Valentine’s Day is a good reminder. Begin spring fertilization right after you prune them. Roses are heavy feeders, so continue to feed them every month during the growing season using a balanced fertilizer, e.g.10-10-10. (NOTE: Since our Denton County soil tends to retain phosphorus and potassium, it is recommended that you perform a soil test annually or every second year before adding more of those minerals.)
Question: My roses have black spot. Is there anything I can do? (May 4, 2018)
Answer: This fungus is one of the most common rose diseases in the world. Unfortunately, if allowed to continue unchecked, your roses will become weak and susceptible to insects and other diseases. The best prevention is to look for black spot resistant rose varieties.
When leaves remain wet for 7+ hours, the fungus germinates, and splashing water spreads the spores to other leaves and canes. Since the disease depends on wet conditions, the heat of July and August inhibit the infection. Our typical wet, humid spring, however, is ideal for its spread.
If you can limit overhead watering, do so. If you do water with overhead sprinklers, do so in late morning so that the leaves will dry quickly. Remove the infected leaves and canes as soon as you see them. It is better to dispose of this material than to compost it.
The fungus survives the winter in fallen infested leaves. To minimize overwintering, collect and discard the diseased leaves in the fall and cover the area with mulch.
Fungi are hard to kill, so the goal is to control the infection as best you can. There are several fungicides (even some that are organic) that will help, but they must be used every 7-14 days. As we always caution, follow directions as stated on the label.
The following article contains more information about specific fungicides.
Question: Dozens of Cora vinca I planted in April are yellowing, wilting and dying! Could it be a fungus? I thought the Cora vincas were immune! What did I do wrong? (June 14, 2019)
Answer: Oh, the heartbreak of vincas and fungus! I feel your pain and can help you sort it out.
First, what you did right: Selecting Cora series vinca! These Texas Superstar darlings emerged from years of trial garden study to address the chronic fungal issues of the vinca. The Cora series plants were named after Cora Van Wingerden – the matriarch of one of the most notable horticulture families in the US. With the steadfast character traits of their namesake, Cora vincas thrive in summer’s heat.
Now, let’s explore what went wrong. Early planting undoubtedly contributed to your troubles. These heat-loving annuals must not be planted before late May in Denton County. Unfortunately, the plants appear in garden centers in April, so we are tempted to plant early. Wait for late May, even June!
Next, we need to address immunity vs. resistance. These plants are NOT immune to fungal infection; they are RESISTANT. If environmental conditions favor fungal growth, even this new variety can succumb. As a preventive, use fungicides labeled for control of Pythium sp., Phytophthora sp., and Rhizoctonia sp. in vincas. Read labels completely and follow all instructions.
Poor irrigation and drainage contribute to the dreaded “f” word infestation. If using overhead sprinklers, water early so leaves dry by late morning. Drip irrigation is preferred. Use several inches of mulch to keep wet soil (and spores) from splashing onto leaves. With regard to drainage, vincas don’t tolerate “wet feet.” To sum up, they fare best with dry leaves and occasionally damp roots.
Next spring, do not plant any variety of vinca in the same beds. Research annuals that tolerate being planted earlier in spring and that are less susceptible to fungus. Use them in alternate years to the vincas.
Links for further reading:
- Disease ID and management:
- Earth Kind plant selector:
- History of Cora vinca development:
Question: Every spring, when monarch butterflies pass through Texas on their migration, I always wish my landscape had more plants helpful to them. Is it too late to plant milkweed? What varieties are best? I heard tropical milkweed can be a problem.
Answer: You’re not alone in your fascination with monarch migration and life cycle. To assist in this miracle of nature, plant only native milkweeds. Recommended varieties for north Texas:
Antelopehorn (A. asperula), Butterfly milkweed (A. tuberosa), Green antelopehorn (A. viridis), Zizotes (A. oenotheroides)
Although monarch butterflies enjoy nectar from many types of flowers, Monarch larvae feed exclusively on milkweed, so it must be available in spring when females lay eggs. To nourish both migrating butterflies and their offspring, incorporate other plants that flower in a staggered timetable so nectar is always available. Fall flowering plants are equally as important since the final, migrating generation will need food sources for its journey south. Click here for info on Monarch Lifecycle
Ideally, native milkweed should be planted by March for spring migration. However, since milkweed is a perennial, go ahead and plant it. Although your new planting may not help this year’s migrating butterflies, it will give this year’s first-generation offspring a host plant for the second generation, and so on. Click here for info on Creating a Monarch Habitat
Conventional nurseries occasionally carry the native milkweeds; a better option might be to look for retail nurseries specializing in native plants. Scour local plant sales and ask fellow gardeners if they have some to share. Consider propagating your own once you have a supply. Alternatively, look for reputable mail-order sources. Click here for Native Seed Finder
Non-native, tropical milkweeds should not be planted. In more temperate climates, they may encourage year-round monarch colonies, which is undesirable for the species. Also, the long life of the native plant in warmer areas (San Antonio and southwards) can provide shelter to a protozoa harmful to the monarchs. If you already have a tropical milkweed in your garden, consider replacing it with a native. If you can’t bear to part with it, cut it back to a 6-inch stalk in the early fall and continue to trim new growth until winter causes dormancy. It will grow back in the spring. Click here for Risks of Growing Non-natives.
Trees and Shrubs
Question: I have pine bark beetles on my pine tree. Will they kill my tree? How do I treat them to get rid of them?
Answer: Three beetle species may be present in southern pine trees: Black turpentine beetle (Dendroctonus terebrans), Engraver beetles (lps species), Southern pine bark beetle (Dendroctonus frontalis). It is crucial to determine which type of beetle has attacked your tree because the first two don’t usually kill the tree, but the southern pine bark beetle attacks pines of all sizes and can kill healthy trees.
Common Pine Bark Beetles
Unlike wood-boring beetles, bark beetles do not bore into the tree’s wood. They chew holes through the bark and feed and lay eggs between the bark and the wood.
The black turpentine beetle is attracted to pine sap that may be oozing from an injured tree. The damage they cause is similar to the engraver beetles and southern pine beetle; however, it typically does not cause rapid decline and death of infested trees. The adult is 1/4 to 1/3-inch long, dark brown or black, with a rounded abdomen. The pitch tubes (glob of resin) are found on the lower trunks or stumps of pines. The pitch tubes are large, greater than 1/2 inch in diameter. The galleries are “D” shaped.
The engraver beetle species can usually be spotted by the presence of reddish-brown boring dust in the crevices of the bark. The pitch tubes, or globs of resin, will have a reddish-brown appearance because of the boring dust mixing with the resin. Engraver beetles tend to attack the flat bark plates of the tree. The brownish-red beetles make “H” or “Y” shaped galleries. Three species of engraver beetles vary in size and physical characteristics.
– Ips avulsus , the smallest Ips beetle, is 1/8-inch long with four projections on the posterior of each elytron. This species tends to invade the upper portion of the tree.
– Ips grandicollis is the medium-sized bark beetle, which is about 3/16-inch long and has five projections on the posterior of each elytron. This species commonly invades the middle and upper trunk.
– Ips calligraphus is about 1/4-inch in length and has six projections on the posterior of each elytron. The beetle characteristically attacks the lower trunk.
Like the black turpentine beetle, the engraver beetle species typically does not cause rapid decline and death of infested trees.
The southern pine bark beetle can be detected by observing masses of pitch (pitch tubes) on the bark of dying pine trees. The adult beetles are tiny, 1/16 to 3/16 inches. A small notch can be seen on the front of the head with a magnifying lens. They tend to attack the middle and lower trunk of trees. Their galleries are “S” shaped.
As noted earlier, the southern pine bark beetle can cause injury that results in rapid decline and death of the tree. Needles of infested pines will initially turn yellow, then red, and ultimately drop off. Masses of reddish-brown pitch (resin) appear on the bark, white dust from boring appears in the bark crevices, under the bark, and at the base of the trunk. The galleries girdle the tree, and a blue stain fungus causes the tree to die quickly.
Maintaining healthy trees is a homeowner’s best policy for preventing beetle attacks. Watering trees (slow and deep) is important to avoid beetle attacks. Remove visibly infested trees promptly, and take care to avoid damage to uninfested trees.
According to Texas A&M Forest Service, “During the fall, it is natural for pine trees to develop small “flags” of yellow and red needles scattered through the crown of the tree. Also, discoloration of the second year needles (needles away from the end of a branch) occurs in the fall and during drought stress. These needles may persist on the branches, and needles that drop from upper branches may lodge on lower branches. This tends to give the tree’s foliage an off-color or unhealthy appearance. In addition, an entire branch in the lower crown (usually a bottom branch) may die in the fall of the year. This is normal and does not indicate that pine bark beetles are beginning to attack the tree. However, the casual observer may MISTAKENLY think the tree is succumbing to pine bark beetles.”
A topical insecticide spray is the preferred method of treatment for pine beetles. Applying these insecticides is not practical or safe for a homeowner to attempt. If an infestation of pine beetles is suspected, contact a certified arborist to confirm and treat or remove the infested tree(s). Find a certified arborist that works in your area by clicking this link on the International Society of Arboriculture website: https://www.treesaregood.org/findanarborist/findanarborist .
Learn more about pine beetles at these websites:
“Forest Health: Southern Pine Beetle or Pine Engraver or Ips Bark Beetle,” Texas A&M Forest Service, https://tfsweb.tamu.edu/PineEngraverOrIpsBarkBeetles/
Question: If I get a live Christmas tree to plant later in the yard, will it survive?
Answer: Thank you for contacting Denton County Master Gardener Association. The general answer to your question is, “Maybe”. The Douglas, Fraser and Noble firs that are staples of the cut Christmas tree market are used to living in colder climates than North Texas provides. However, there are a few varieties of living Christmas trees you can use indoors for the holidays and then plant in your yard.
- Semi-dwarf Blue Atlas cedar (Cedrus atlantica ‘Horstmann’): Gray-green to blue-green foliage, 8-15 feet tall, 5-6 feet wide
- ‘Skyrocket’ juniper (Juniperus scopulorum ‘Skyrocket’): Blue-green foliage, 15-20 feet tall, 2-3 feet wide. (Also called Rocky Mountain juniper)
- ‘Brodie’ red cedar (Juniperus scopulorum ‘Bordie’): Dark green to bright green foliage, 25 feet tall, 6-8 feet wide
- Arizona cypress (Cupressus arizonica): Sage-green to blue-gray foliage, 20-30 feet tall, 8-12 feet wide
Texas A&M AgriLife Extension Service also recommends considering Leyland cypress (Cupressocyparis leylandii). “The Leyland Cypress is an excellent choice for a living Christmas tree which should provide beauty for years to come. Even though the Leyland Cypress does have the “Cypress” name, it is similar to a juniper bush than a Bald Cypress tree. It should be planted in a full sun location and will require about the same care a juniper does — very little! Plant it as soon after the Christmas holidays as you can so it can establish a root system before spring growth begins. DO NOT let the root ball dry during its stay in the house. Dead trees do not grow well even if they are planted outside.” https://aggie-horticulture.tamu.edu/archives/parsons/trees/leyland.html.
And, the Texas Forest Service adds, Afghan Pine (Pinus eldarica) as a living Christmas tree option. A medium-sized, pyramidal pine tree that when mature can grow to 40 feet tall. The Afghan pine tolerates alkaline soils unlike many pine tree varieties that prefer acidic soil.
It is best to keep your tree indoors for as short a time as possible. Make sure that the root ball is kept damp, but not dripping. When you are ready to add the tree to your landscape, identify a sunny location that has enough space for the mature tree. For detailed instruction on tree planting, “How to plant a tree” provides guidance. (https://dcmga.com/north-texas-gardening/trees/how-to-plant-a-tree/).
Question: Now that most of the leaves have fallen off my oak tree, I see mistletoe is growing in the top branches. Will this kill my tree? What can I do to get rid of it?
Answer: Mistletoe ( Phoradendron spp. ) is a popular Yuletide decoration. It was once believed to have magical powers and medicinal properties. The custom of kissing under a cluster of mistletoe leading to marriage started in England. What’s found here in the U.S. is typically referred to as American Mistletoe. It’s noticeable on oaks, pecans, and hickories after leaf fall but can be found on 100s of other hardwood species as well.
Although mistletoe will not typically kill a tree, a heavy infestation can contribute to poor tree health, particularly if other problems stress the tree. It can cause branch death, and reduce the vigor of the tree and stunt its growth. Mistletoe’s white berries are poisonous and may cause stomach and intestinal irritation. Keep mistletoe away from children and pets.
What is mistletoe?
American mistletoe is an evergreen parasitic plant found on certain woody plants, primarily hardwood and broadleaf trees. The female plants produce seeds in a white, sticky gel-like substance that sticks to the bark. When the seeds germinate, they create a root-like structure (haustoria) that penetrates the bark on small branches through a bud or lenticels (pores in the stem of a woody plant). The mistletoe pulls water and nutrients from the host tree. It is found high in the crown of trees because it requires direct sunlight to produce food through photosynthesis. It grows the first year slowly, expanding up to 3 feet in 6 to 8 years.
Can mistletoe be controlled?
Mistletoe has few natural enemies. The most effective control is to remove the infected limbs with thinning-type pruning cuts. To remove the embedded haustoria altogether, the infected limbs should be removed at the point of origin or back to the lateral branches, at least 1 foot below where the mistletoe is attached. Because mistletoe grows at the top of the tree, it is best to hire a certified arborist to do this work. They have the training and equipment to accomplish this safely.
Topping or heading the tree is not recommended because this weakens the tree structure. Removing the wood tissue or bark where the mistletoe is attached can cause more harm to the tree than the mistletoe!
Cutting the mistletoe out of the tree is better than doing nothing. Although it will grow back, this does reduce the spread. This is best done before it produces seeds and spreads to other limbs or trees.
A severely infested tree may need to be removed and replaced with resistant species such as Chinese pistache, crape myrtle, ginkgo, golden raintree, sycamore, or conifers.
Application of herbicides high in the crown is dangerous, and the drift can damage nearby plants. A plant growth inhibitor with the active ingredient ethephon is the only registered product in the U.S. for mistletoe control. Apply the product in the spring before the tree leaves out when the temperature is above 65 degrees. Thoroughly wet the foliage of the mistletoe with the product, but not the entire tree. Repeat applications will be necessary. Again, hiring a certified arborist is recommended.
The bottom line
The best prevention is to plant naturally resistant tree varieties. If control is necessary, engage a certified arborist to accomplish this safely. You can find a certified arborist that services your area at this link from the International Society of Arboriculture https://www.treesaregood.org/ .
Learn more about mistletoe at these websites:
Question: I wanted to plant an Empress tree but I was told that it is an invasive species. Can you tell me what that means? The tree is beautiful. Should I really care?
Answer: The Empress or Princess (Paulownia tomentosa) tree you mentioned is a survivor. It can regenerate after it has been cut down, burned, or bulldozed. But it doesn’t just survive; it thrives. Producing up to 20 million seeds a year, it reproduces prolifically. Is that a bad thing? Yes, because we live in a fragile ecosystem that can be disrupted. The problem with invasive species is that they can outcompete native plants and prevent them from surviving. Invasive plants have negative ecological, environmental, and economic consequences.
A healthy and diverse plant community consists of a variety of herbs, shrubs and trees. Invasive non-native plants, having few predators, can outcompete and displace native flora that are necessary food or cover for native wildlife. Or, the loss of diversity may reduce the quality of habitat for fish and wildlife so that they become weak or even extinct. Japanese knotweed and kudzu, for example, may displace all other forms of vegetation, creating a monoculture.
Large monoculture areas are more likely to erode during flooding than areas with a diversity of plants because there is less root structure to hold the soil in place. Excess erosion releases sediments to streams, leading to a degradation of water quality.
Monocultures can also create fuel for wildfires. For example, English ivy growing up a tree to the canopy allows fire to reach the top of trees, which makes the fire harder to control. Some invasive grasses become dry and dormant in summer, making them a fire hazard.
Some estimates are that invasive species cost as much as $120 billion per year in lost crop and agriculture production, removal costs, and reduced export potential. In other words, farmers pass along the cost of controlling invasive species by increasing the cost you pay for vegetables or meat.
What native flowering trees you can plant instead:
- Southern Magnolia (Magnolia grandiflora)
- Desert Willow (Chilopsis linearis)
- Texas Redbud (Cercis Canadensis var. texensis)
- Mexican Plum (Prunus mexicana)
List from Ladybird Johnson Wildflower Center of native plants for North Central Texas: https://www.wildflower.org/collections/collection.php?collection=TX_northcentral
North Central Texas Native Landscape Certification Program (NLCP) Plant List Spreadsheet Native Plant Society of Texas (NPSOT): https://npsot.org/plant_lists/NorthCentralList.pdf
Question: I believe I should be spraying my peach and plum trees during the winter. Could you help me with what spray I should use and when to apply them?
Answer: Some treatments should be applied during the dormant season (winter) for both fruit and pecan trees. For pecan trees, dormant season treatments are for scale insects, mite eggs, and phylloxera. Dormant season treatments for peach and plum trees are for scale insects and peach leaf curl. Let’s focus on treatments for fruit trees.
What are scale insects? Scale insects are unique because they create protective armor as they grow. They overwinter on the plant and begin to reproduce in the spring. They feed on nearly all parts of the fruit tree – bark, leaves, and fruit. They can cause stunted growth, leaf drop, fruit lesions, and even the death of branches or entire trees if left untreated.
They often look like small warts or bumps on the tree’s bark. The female insect is sucking sap from the plant and laying eggs underneath the protective armor, hidden from view. There are many species of scale insects, ranging in size from 1mm to 3mm, and are usually circular or oval-shaped. Their color range is also broad, from white to brown to red or orange; some are spotted or striped.
White peach scale insects (Pseudaulacaspis pentagona) and San Jose scale insects (Quadraspidiotus perniciosus) can be problems on peach, nectarine, apple, pear, cherry, and plum trees. Scale insects look like small bumps on the branches and trunk of the tree and can blend in with the texture of the bark. The white peach scale is white with a yellow-orange color, and the San Jose scale is white.
What is the treatment for scale insects? Applying 97% dormant oil during the winter months is an effective treatment for scale insects. It’s much easier to thoroughly coat the tree’s trunk and branches during the dormant season when there are no leaves on the tree. The oil seeps under the scale’s protective cover, coats the insect and eggs and smothers them. Dormant oils are safe and easy to apply and have little impact on beneficial insects.
Apply dormant oil when the temperature is between 40 and 70 degrees and at least 24 hours before or after rain or freezing temperatures. Follow the packaging label for the concentration mixture, which can be a higher rate during the winter months. Thoroughly coat all the bark surfaces, paying particular attention to the nooks and crannies of the tree where scale insects like to congregate. Plan to repeat the application in 2 – 3 weeks.
Peach leaf curl (Taphrina deformans) can also be treated in the late dormant season if there’s been a history of leaf curl. Apply a copper fungicide or Chlorothalonil following the packaging instructions. Learn more about peach leaf curl disease at this website from Texas A&M AgriLife Extension: https://aggie-horticulture.tamu.edu/newsletters/hortupdate/hortupdate_archives/2002/mar02/art9mar.html
Learn more about fruit and nut spraying for homeowners and controlling scale insects at these websites:
Question: I live in Melissa (Collin County) and have two trees in the front yard that are alive, but look diseased. There are large cracks down the trunks of the trees. Do you have any recommendations? I would greatly appreciate any advice.
Answer: Thank you for contacting the DCMGA Help Desk. What you see looks more like sunscald or sunburn than freeze damage. The damage is not repairable but is preventable. Here’s some information about what causes sunscald or sunburn in trees and how to prevent it.
What is sunscald or sunburn in trees? Sunscald or sunburn in trees is the death of the tree’s cambium tissue (living cells just under the bark) on the trunk due to high or rapidly fluctuating temperatures. There are two times of the year this can happen – winter and summer. Although not a common occurrence in Texas, sunscald in winter is caused by rapid fluctuations in temperature. The cambium tissue on the south or southwest side of the tree’s trunk warms from the sun’s heat then rapidly refreezes, likely during overnight freezing temperatures. Sunburn is more common in Texas. High summer temperatures can kill the tree’s cambium tissue from sun exposure on the south or southwest side of the tree’s trunk.
What are the symptoms? In the early stages, sunscald or sunburn can be difficult to detect. The bark on the south or southwest lower portion of the trunk may discolor and some cracking may be visible. Oozing or “bleeding” from the damaged area may appear in the spring. Eventually, the bark will begin to slough off.
In the late stages of damage, cracks or gaps in the bark down to the xylem tissue (interior wood) will appear. There may be evidence of wound healing on the margins of the crack. The loose bark can be carefully removed, but do not tear into or cut into the interior wood tissue. Insects may be visible in the cracked area. Pruning paint should not be applied to the wounded area. Extreme damage can lead to the tree’s death or weakening of the trunk’s strength resulting in breakage.
What types of trees are susceptible? Young or thin-barked ornamental or fruit trees are susceptible to this type of damage. Examples of susceptible tree varieties include maples, fruit (peach, apple, plum), linden, ash, honey locust, Eastern white pine, Texas redbud. In addition, drought-stressed or newly transplanted young trees are more susceptible. Evergreen trees are less susceptible to winter sunscald because the foliage shades the tree’s trunk.
Can sunscald or sunburn be prevented? In Texas, the most important method of prevention is to keep the tree healthy and vigorous with proper watering during the dry hot summer months. Trees should be deeply watered at a minimum of 1 inch of water per week if there is no rain during the growing season. A few deep waterings (1 time weekly) will encourage deep root growth. Frequent shallow watering (2+ times per week) encourages shallow rooting leading to damage during drought.
Some other prevention methods:
- Wrap the lower trunk of young, thin-skinned trees with light-colored materials such as kraft paper or breathable white fabric tree wrap. Be sure not to girdle the trunk when installing the wrap, e.g., do not use wire or zip ties to hold the wrap in place. Leave the wrap in place for several years until the bark is thick and textured enough to withstand extreme temperatures or the canopy of the tree is large enough to shade the trunk.
- Avoid transplanting trees during hot summer months. The ideal time to plant trees in North Texas is late fall to early spring.
- Apply a 1 to 2-inch layer of mulch in the root zone of the tree, keeping the mulch away from the tree trunk and root flare. The trunk and root flare should be exposed.
We recommend engaging a certified arborist to help assess the health of your trees. To find a certified arborist that works in your area go to this website from the International Society of Arboriculture: https://www.treesaregood.org/findanarborist.
If you determine you need to replace your trees, this site from Texas A&M Forest Service will help you find the best tree for your landscape: https://texastreeplanting.tamu.edu/.
Check out these websites to learn more about sunscald and sunburn in trees:
“Sunscald on Trees” (2021). University of Arkansas Cooperative Extension Service: https://www.uaex.edu/yard-garden/home-landscape/trees/sunscald-on-trees.aspx
“Environmental Injury: Sunscald and Sunburn on Trees” (2016). Washington State University Extension. http://pubs.cahnrs.wsu.edu/publications/wp-content/uploads/sites/2/publications/fs197e.pdf
Question: What is wrong with my Italian cypress? They’re turning brown and thinning out.
Answer: These beautiful trees suffer a number of problems in north Texas. Often, environmental stressors make the trees more susceptible to fungi, spider mites and root rot. I will include links with information on these conditions so you can better decide what may be troubling your trees. Remember that more than one issue can be at play.
In the first link, below, read about seiridium canker, bot canker and cercospora blight, all of which are fungi. Only cercospora is treatable with a copper fungicide. No chemical treatment is available for seiridium and bot cankers, which are usually fatal for the plants. However, selective pruning and proper clean up of diseased plant material will help slow the progression of the problem. When pruning out the diseased portions of your trees, clean pruners with a 10% bleach solution between each tree. Rake up all dropped plant material and dispose of it in regular garbage; do not compost.
You might consider mailing a sample of plant material for analysis to the Texas Plant Disease Diagnostic Laboratory in College Station to confirm what pathogen you’re seeing. Minimum charge per sample is $35. I will include a link, below, to the submittal form. Make sure to note in the “comments” section that you’re looking for cercospora. I wouldn’t have a lab test for seiridium or bot canker, since neither of these conditions are treatable by fungicide or other chemicals. Since cercospora is treatable, you’ll want to confirm its presence before spending money on fungicide application, which will require a certified arborist’s assistance in tall Italian cypress.
Certified Arborists Only
If your trees have cercospora, only hire a certified arborist to apply a copper fungicide. Do not give in to the temptation to hire the average landscaper. If your trees cannot be saved, do not replace them with more Italian cypress or other trees known to be troubled by the identified fungus.
If your trees have been overwatered or if the soil drains slowly, consider phytophthora root rot, a mold. This is a less likely culprit, but worth reading about, as well. Make sure to monitor the soil moisture surrounding these trees, which do best in well-draining, even dry, locations. Commercially available fungicides labeled for use on phytophthora are available, but will only be effective if used in addition to correcting drainage. See link, below, for more information.
Read about spider mites and treatments in the two links, below. It should be fairly easy to detect the mites, especially as the season heats up. Hold a white piece of paper under the affected branch and shake. If mites are present, you’ll easily see them when they fall onto the paper.
Spider mites can be battled a number of ways:
- …with the introduction of specific, predatory insects/arachnids,
- …with mechanical controls like a strong sprays of water from a garden hose, or
- …with organic or synthetic chemicals, like horticultural oil, insecticidal soap, and insecticides. (Read the label to make sure the product is intended for spider mites.)
Bear in mind that either type of chemical treatment can kill beneficial insects along with the spider mites. “Beneficials” often feed on the mites and keep their numbers down, so if we lose beneficial predators, the mite infestation could worsen.
General information about problems in Italian Cypress:
See the photo of seiridium canker lesions in this document: http://entoweb.okstate.edu/ddd/diseases/Seiridium.htm
Texas Plant Disease Diagnostic Laboratory webpage: https://plantclinic.tamu.edu/
Question: I moved into Argyle just over a year ago, and this spring we are planning to plant about 20-25 trees on our property. My question is that with the recent extended hard freeze, are larger container (30g-60g) trees at more risk of root damage as compared to ground dug trees. I understand that ground dug trees can lose 25-40% of roots during transplant, and I am still leaning towards the larger container (30g-60g) trees. Any information and ideas that you can share are appreciated.
Answer: What a wonderful question! To answer it, let’s cover three things: types of tree roots, damage to tree roots by cold temperature, and what to look for in choosing nursery trees.
Types of Tree Roots
- The youngest roots of a tree are referred to as the primary roots.
- The intermediate size roots are the secondary roots. It is important to note the health of secondary roots is the most critical for the tree’s survival.
- The tertiary roots are the most mature.
Cold Temperature Damage to Tree Roots
- The youngest roots (primary roots) of a container or balled and burlapped trees are most likely to be damaged by freezing temperatures because they are located on the outside edge of the container or burlap wrapping. Injury to these roots may cause growth in the spring to be reduced and uptake of nutrients can be affected if the damage is extensive. Young roots can regenerate quickly, however.
- Injury to secondary roots (intermediate size roots), depending on the extent of the damage, is the most critical factor in the survival of the tree. Growth in the spring will be reduced due to secondary root damage. If the damage to these roots is severe, the tree’s growth may appear to be normal, but the tree will die quickly in the heat of summer.
- Damage to the mature roots (tertiary roots) will nearly always result in the death of the tree.
What to Look For
Most of the tree’s roots grow in the top 6 to 24 inches of the soil. Check for the following in this area:
- Damaged roots will most often appear to be much darker in color than healthy roots. Check the health of all 3 types of roots – primary, secondary, and tertiary. If secondary or tertiary roots are damaged, it may be best to pass on purchasing the tree.
- Check for circling or girdling roots. This most often happens in container or ball and burlapped nursery trees, but can also be found in ground-dug nursery trees.
- Wounds or injury to the trunk.
Normally, you would also check for yellowing or damaged foliage. However, the foliage of many trees was damaged due to winter storm Uri. The advice from Texas A&M AgriLife is to wait a few weeks to see if the tree rebounds.
Irrespective of whether you purchase ground-dug, container, or burlapped and balled trees, you should purchase them from a reputable nursery and carefully inspect the trees’ health.
You may also find these resources helpful:
Additional Sources & Resources
Management of Container Nursery Plant Material During Cold Weather (February 2015,, Jim Johnson, Agriculture and Natural Resources Agent, Cumberland County, Rutgers New Jersey Agricultural Experiment Station, https://njaes.rutgers.edu/fs528/
Question: Should I prune away the freeze damage done to my plants and trees?
Answer: “Watch and wait” is the current recommendation from the Texas A&M Agrilife Extension Service. Do not be tempted to prune or fertilize these stressed, damaged plants yet; once you prune, new growth may flush out on some plants. Since the last average frost date in north Texas is mid-March, the new growth could get damaged by low temperatures still possible in late winter. Fertilizers and pre-emergence herbicides will be stressors as well, so postpone these treatments a few weeks longer than usual. In general, the plants and trees need time to recover from the severe cold stress.
We understand the frustration you may feel when hearing “watch and wait;” it is a broad statement. However, no harm will be done if you wait until after the last average frost date, but some harm is possible with premature pruning. The only exception to this guideline would be pruning for safety’s sake. Branch damage in large shade trees could pose a risk to people, pets, property and adjacent power lines, so cracked branches should be removed.
Warning: If you prune oaks this time of year, pruning cuts must be immediately painted with wound dressing to protect from oak wilt. From February to July, the beetle that spreads oak wilt fungus is active and foraging. When you prune oaks at this time, you’re basically ringing a dinner bell for these insects, who feed on tree sap. The beetle can carry the fungal spores from a diseased tree to countless healthy trees, leaving behind silent spores to do their damage, which is fatal in many cases. Here’s a website for more information on preventing oak wilt:
During the next few “waiting” weeks, put your energy towards plant recovery. In particular:
- Have a soil sample analyzed by the Texas A&M Soil Sampling Lab, if you’ve not done so in the past year. Collect one sample from your turf and a second sample from your landscape beds. The lab will make a recommendation on what nutrients and quantities are needed for each area, as they will likely differ based on what you’re growing. These tests are inexpensive and invaluable this year, especially. Check the links below for soil submittal form/instructions and a great article on understanding fertilization recommendations:
- If you have a sprinkler system, complete an audit of the system yourself or hire a licensed irrigator. Pipes and sprinkler heads may have cracked due to the freeze or to regular wear and tear. An audit is quite easy. Simply run each zone long enough to check every sprinkler head or emitter in the zone. Any repairs can be completed before the growing season gets fully underway. Some cities employ licensed irrigators who can be engaged to conduct the audit at no charge via the city’s website. Repairs remain the responsibility of the homeowner. More information on proper irrigation:
- Prepare to selectively prune damaged plants and trees after growth begins (which could be May or June in some cases). You may be surprised how many latent buds spring to life! Read more, below:
- Damaged trees, turf and plants are stressed. Stressed trees, turf and plants are more susceptible to disease and pests. Keep watch for evidence of disease or pests so you can treat the problem quickly. Make sure to monitor moisture more closely, as well. Avoid the extremes of drought or drowning! Use the links below for details:
- “Watch and wait” for turf, as well. If you have appreciable damage, consider using four- to six-inch plugs of turf from a healthy section of your lawn to fill in the gaps left from the freeze. You’re more likely to see cold damage in centipede and St. Augustine. Bermudagrass is the next most cold tolerant turf, with zoysia being the most cold-hardy turf used in our area.
- Also, in turf, consider having the most damaged areas aerated and top-dressed with compost after vigorous growth begins. Small hand aerators will do the trick for limited areas, but you can also hire someone to aerate for you, if the area is large or if that’s your preference.
- With large shade trees, look closely, even with binoculars, to check for cracked branches caused by the weight of snow or ice. The danger of a falling tree branch cannot be over-stated. If you cannot safely remove damaged branches yourself, hire a certified arborist to inspect your trees and prune any cracked branches. Some arborists will make site visits for free; others charge a fee, which is usually applied to any work done. Make sure to ask. If emergency pruning of oaks must be done from February through June when oak wilt is a risk, immediately paint the raw wood with wound dressing paint. During the remainder of the year, no wound dressing is recommended. Here’s a link to find a certified arborist near you:
Published by Texas A&M Agrilife Extension specialists in the week after the storm, the YouTube video linked below gives details on freeze recovery. Look for “Chat with Green Aggies” on YouTube. The discussion is more oriented towards those in the horticulture business, but much of the information is applicable to the homeowners, as well.
The same group of Extension professionals published an “emergency session” video on storm recovery two weeks after the initial storm. “Winter Recovery for Plants” on the Chat with Green Aggies page can be viewed now on Facebook. If you do not use Facebook, you can view the recording early next week on the “Chat with Green Aggies” YouTube page. Here is the Facebook link to the video:
Larry Stein, Agrilife Extension horticulturalist, published this video after the storm. He also warns against premature pruning, and explains how to tell if a branch may be more likely to produce new growth after damage. It should be of further assistance to you:
Answers to questions particular to your landscape can be found by contacting the Denton County Master Gardener Help Desk at the link below:
Question: Should I remove the stakes and straps from the peach tree I planted last year? Also, can you tell what bored holes into the trunk, and do I need to treat it with anything?
Answer: Definitely remove the stakes and straps! They protect the tree in the first few months after planting. Within six months, the new root system takes over and anchors the tree instead. In fact, the stress placed on a tree through wind pressure actually strengthens and thickens the trunk…think of it as a workout for your tree!
The stakes and straps currently in place were likely the original ones installed in the nursery when the tree was very young. You’ll notice that as the tree has grown, the green strapping has tightened. In time, this strapping will cut into the bark and damage the tree, so I would remove all the strapping now.
I also noticed that the bark has begun to grow around the stake. (I circled the areas of bark swelling in your original photo, so you can see what I mean.) Just as with the strapping, the stake will damage the bark and risk the health of the tree. I would carefully remove the stake now. Don’t worry about the part of the stake underground; in fact, it might have rotted, anyway. If it pulls up easily, great. If not, please do not force it.
Bear in mind, though, that sometimes the prevailing wind is so unrelenting in some locations that another stabilizing method can be used. Several options exist, all of which will protect the tree without damaging the trunk or inhibiting its growth. See the third link, below, for details.
Now, on the subject of the holes in the trunk. This pattern is typical of woodpeckers, flickers and sapsuckers, especially in spring when they are seeking a mate. The damage to your tree doesn’t look severe, so no treatment is necessary. However, if you hear the birds drumming away at the bark again this spring, there are deterrents you can put in place to discourage the birds without harming them, while simultaneously protecting your tree. The fourth article linked below explains the process.
Best wishes in moving toward a great peach harvest one day!
Question: Hello. Hoping to get guidance on when to prune my new plum trees. just (11/6) planted 3 nursery plum trees. My plan is to prune them to remain manageable. I’ve seen several sources that advise aggressive (2′ tall trunk) pruning immediately after planting. I also see that early spring pruning is the best timing. I want to strike a balance between achieving the initial cut and ensuring that the tree has adequate nutrients stored in the roots over the winter. Should I cut now or hold off until Feb/March?
Answer: Thank you for contacting the Denton County Master Gardener Association Help Desk with your question about how and when to prune young plum trees.
I understand it seems risky to aggressively cut back a newly planted young fruit tree. However, according to Larry Stein, Ph.D., AgriLife Extension fruit specialist, that’s exactly what you should do. Dr. Stein recommends cutting fruit trees to 18 inches to 24 inches and trimming all the limbs back to the stem. Cutting back in this way will force the tree into growth mode to help it develop a strong root system. This pruning should be done in winter while the trees are dormant.
Dr. Stein recommends some additional steps to take to help your trees be productive:
- Remove all grass and weeds within a 2 ft to 3 ft diameter around the trunk of the tree. Keep this area clear for the first five years to reduce competition for water and nutrients. After the first year, apply 3 inches of mulch over the root zone, leaving a 4 to 6 inch gap between the tree’s trunk and the mulch.
- Getting a soil test to identify the nutrients that may be needed is a really good idea. This link on the Denton County Master Gardener Associate website provides more information about soil testing and the steps for getting one done. https://dcmga.com/north-texas-gardening/community-gardening/soil-testing/
- Deeply water your trees once every 4 to 6 weeks during the winter and spring absent rainfall, and then weekly during the hot summer.
- During the first year fertilize your trees in April following the soil analysis recommendations, then again in May, June, and July with high nitrogen fertilizer (NPK 21-0-0).
- You will not likely need to prune your trees the first year. In the subsequent years prune using the open system pruning method which ensures sunlight reaches all the limbs of the tree and fruiting over the whole tree. Aggressively prune only when the tree is dormant in the winter before bud break. Prune lightly any time of the year.
- Manage insects and fungus with a regular spray schedule using a residential fruit tree spray that contains an insecticide and fungicide.
These two articles from Texas A&M AgriLife Extension will help you get off to a good start.
With the right care, you should have a bountiful harvest of plums for years to come!
Question: Several hackberry trees next to our house are infested by gnat-like bugs. In addition, the trees’ leaves have nubby bumps on them and are falling early this year. Are the bumps and bugs related? Thousands of these insects are crawling on our windows. How do we manage this infestation and save our trees?
Answer: The nubby bumps on your hackberry tree leaves are called hackberry nipple galls. It is a common but non-fatal condition in hackberry trees caused by an insect called a “psyllid” (SILL-id).
The bugs on your windows are likely the psyllids responsible for the galls. While these are nuisance bugs, they do not bite/sting and are not harmful. They are most abundant for a few weeks in the fall. Although they are small enough to pass through window screens, they will neither breed nor set up a “nest” in the house. They are simply seeking warmth. If the bugs become too troublesome, the recommended “treatment” is the removal of the trees, which is probably too drastic a measure for the other benefits offered by these native specimens. It may be better to simply keep the windows closed when the psyllids are active.
Alternatively, you could attempt to kill/disrupt the bugs with a strong spray of water from a garden hose (if your windows won’t leak!). On a cold day when the psyllids are more sluggish, you could swat large swaths of them with a damp rag (if it won’t damage your glass or screens.) Pesticides are not recommended unless you experience severe or long-lasting infestation. Keep track of how long the infestation persists. It likely will not last long enough to warrant the expense and adverse unintended consequences of pesticide treatment.
Below is a link on hackberry nipple gall and the life cycle of the psyllid: https://extensionentomology.tamu.edu/insects/hackberry-gall-makers/
Question: Our home has a big oak in the front yard. The root system is now large and a great deal of it is above ground. Is it possible to put soil on top of the roots to restore the yard?
Answer: First, thank you for contacting the DCMGA Help Desk with the question about your oak tree’s root system which is exposed on top of the soil. This problem is seen in many areas in North Texas where mature trees exist. Our “drought and drench” conditions along with your tree’s “personal” environment can exaggerate the problem.
Tree roots require oxygen
Roots of trees need oxygen, and your tree’s roots are coming to the surface to provide the root system with oxygen. The need for root zone oxygen may result from several reasons including heavy clay soils, compacted soils, lack of moisture down deep into the roots, and the tree’s root flare buried too deeply. All these conditions prevent oxygen from getting to the root system as well as possibly preventing water from moving down to the roots.
Expose the root flare
The root flare is where the roots at top of the root system come out of the tree’s trunk. The root flare provides the root system with oxygen. Anything covering the root flare, including soil, mulch, decorative rock, must be removed to expose the root flare and return the tree to a healthy state. Click on the two links below to learn more about the importance of tree root flares: