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Seedlings are sprouting in coco – what now? First grow!

Seedlings are sprouting in coco – what now? First grow!

Edited 5/28, the night before harvest.

Thanks gaiusmarius for all your help and patience.

Hey folks, I put these seeds in the towels just over 72 hours ago and the tap roots showed 24hrs later. Now they’re through the top of the coco and I was wondering what to do now. Anything but wait?

I pH’d my distilled water and moistened the towels. I put 5 White Widow, 5 Aurora Indica, and 5 bag seed between three separate sets of towels and 24 hours later 3 of the White Widow had tap roots about 3/8 of an inch long and 2 of the Aurora Indica had roots about 1/4 inch long. Still waiting on the others from those two groups. The bag seed isn’t doing much but who knows?

I had my rock wool cubes out and ready to use and got to thinking why I should use rock wool when I had Canna coco that is equally as good a medium for sprouting. So I dropped the seeds into holes I’d made in the center of the Solo cups I’d chopped down, covered the holes with a couple of pinches of coco, lightly pressed it down and misted it with more pH’d water. Must have worked OK cause they’re looking kinda happy now. I know I am.

I don’t think I should add anything should I? I have misted them about 4 or 5 times since they started breaking through and I placed the dome lid back on the propagation tray to keep the humidity level up. I lowered my 200W CFL down to within about 6" of the top of the dome. I had a heat mat under the prop tray with a temp control hooked up to it and had it set on 75 degrees while I was trying to pop the beans but turned it off after I put the containers with the seeds in them into the tray. Didn’t want to turn the roots on the new seedlings to mush with too much heat. The light seems to be providing all the heat I need right now. I still have the unsprouted seeds in a plate covered with foil in the prop tray to continue the sprouting process for the other seeds. What else should I do if anything roght now?

I know some on here have had trouble with putting their new seedlings under a dome, but I don’t see the harm as long as I don’t get it so close as to raise the temp under the dome too high. Am I right. If I remember correctly, I shouldn’t give nutes right now, should I?

I’m including pics to show the setup.

The plate with the seeds is in the background, the three White Widow just underneath that, and the 2 Aurora Indica are closest to the camera. The Aurora Indica haven’t broken through yet but their roots were shorter so I expect them any time.

This is the third White Widow and it is barely poking through.

Thanks in advance to anyone who can help out.

Ya got it going on mojo. good job.

DO keep misting them and keep the coco moist, but not too moist so the roots develop. After they get above ground, I give mine a light watering every other day, and may cut that back to every 3rd day, as long as the coco stays moist you should be good. DON’T let the coco dry out. When ya transplant them, try to get a 50/50 mix of coco and perlite.

Remember, coco is a soiless medium, so ya have to add nutes sooner than you would if you were in dirt. Ya don’t need any yet, but I started mine off on MILD nutes as soon as the first true leaves developed. When ya see the cotyledons(sp?) leaves starting to yellow, the seedling has used up it’s stored food and is looking for some more. Like I said, start them off on VERY mild nutes. I used 1/4 strength the first time, and even that was a little strong for some of them

While I’m thinking about it, if you’re starting the seeds in that dome, then covering the plate with foil inside the dome may be unnecessary. Beware dampening off.

Hope somebody with more experience coco wise comes along and helps out, I’m just getting into the coco craze myself, so take my advice with a grain of salt please.


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Thanks for the help guys.

oldpeculiar, I’m going straight Canna nutes. I have on hand Coco A+B, Rhizotonic, PK 13/14, and Cannzyme. I intend to feed light when I start. I saw others giving 2-2.5mL per liter of the A+B but I thought I would go lighter than that – the whole easier to add more than to fix a problem thing I guess. Rather err on the side of conservatism – always good, even in politics, lol. Ooops, that’s another issue, lol.

Also oldpeculiar, unless advised against it, I don’t plan to mix My coco coir with anything. I intend to go with my straight Canna brand Coco Coir. I’ve got the Canna nutes so I wanted to try to grow it without anything added. The coco drains so well and provides so much room for O2 that I don’t think I want to mess with it. I’ve got an open mind though and there are surely more people hear with a lot more experience at this than I (doesn’t take much, hehe) so I’m willing to change. I know the perlite would probably help me by holding onto the water longer and that’s worth considering with the price of these nutes. Speaking of nutes, I would also like to know if the 1 liter sizes of the Canna nutes is going to be enough to see me through this grow or if I should get some more coming.

gaiusmarius, glad you showed up, was hoping you would. I saw in another thread "seedling feeding regime" (think he meant to use regimen unless of course he’s starting a new system of govt centered around pot, which would be kickass!) . In that thread, bongoman said he was going to do the following:

[[[[These new sprouts are getting:

1mL/L of A & B
4mL/L of Rhizotonic
0 Cannazym

Once I get a couple of sets of leaves, I move to this mix:

2.5mL/L A & B
2mL/L of Rhizo
2.5mL/L of Cannazym

Does this sound a reasonable plan for seedlings in Coco? Is it too much of a jump from 1ml to 2.5ml do you think?]]]]

gm, in that thread, you OK’d his recipe. Does this still hold true? I know, in order not to hurt someone’s feelings, I will sometimes approve of somone’s plans they’ve made as long as they not going to hurt themselves in the process. Sort of used the same philosophy raising my two daughters, lol. But since I’m starting with a clean slate and very few preconceived ideas, you’re free to steer me as much as you’re willing. I don’t mind admitting ignorance, it’s easier to do than admit stupidity. Ignorance is fixable with education and constructive criticism but stupidity is forever, lol.

I finally went to bed 5 hours ago and left the dome cover off thinking my mistings needed to be evaporated a little. Woke up, came back to the thread and according to what you had written, I guessed right. One of the Aurora Indica’s is now trying to poke through and the other should be not far behind.

I’ll check my seeds in the plate in a few minutes to see if any of the other seeds have decided to heed the call of their sisters (positive thinking, lol) to join the party. Just checked and not much more yet. One more of the White Widow seeds has split and I can sort of see a little root in the seam. The same for one of the Aurora Indicas. The bag seed looks like it has some white ooze coming out of it about the color of the chemicals that leak out of an old flashlight battery.

Temp in the room is 68.2

And the temp in the tray under the 200W CFL is about 76.

As you can see, the humidity is at about 50% and I think I need more. According to what I’ve read, I need to try for high humidity levels at the beginning of veg and step it down as I go into flowering and through harvest. This afternoon I plan to go get a humidifier.

One more thing, when I transplant, what is the harm in transplanting directly into my 5gal pots instead of going 3gal and then 5 gal. I know it takes less water to water a 3gal but it seems the root growth would be less hindered in the 5gal and doing this would also eliminate the stress to the plants that transplanting heaps on them. Just wondering.

Coco Coir and Cannabis Production

Over the last decade cannabis production has come out of the closet, quite literally. The first person I knew to have grown his own cannabis (or marijuana or pot or whichever name you prefer to call it) grew several pots of it in his bedroom closet, hidden away from his parents. And while some folks may grow cannabis in places unseen by parental and other authorities’ eyes, at-home and/or commercial legal cannabis production is now A-OK in 18 states and Washington, D.C. with more coming on board every year.

If you’re just beginning to grow cannabis legally, you’ll want to grow it correctly. While we won’t get into the day-to-day details of cannabis production here, we will explain how to get your cannabis crop off to the best start possible. It all starts with your growing media (and we know growing media). Specifically, one growing media of choice for many growers is coco coir.

What Is Coco Coir?

Professional cannabis cultivators all agree that drainage and aeration are key to a successful crop. Many achieve this by using coco coir as their growing medium. Coco coir, if you’re not familiar, is produced from the humble coconut, specifically the fibrous material found between the husk and the coconut itself. This material holds water well but also allows for good drainage. (I know it’s hard to wrap your brain around being both water-holding and water-draining at the same time, but let’s chalk it up to science.) Well-draining growing media allows for good air flow, which is good for root growth. And a good, healthy root system is the secret to a great crop of pretty much anything, including cannabis.

Coco coir has another beneficial aspect that is good for not just cannabis but also the planet. It’s a renewable product. Coir’s water-holding-and-water-draining characteristic allows it to be a great substitution for peat moss, which is not a quick-to-renew resource. Less peat being used means less mining, which means less damage to the sensitive and diminishing peat bogs of the northern hemisphere. We came across an article in the New York Times that explains the peat and climate change situation HERE.

The Science of Coir

I mentioned “science” above, and it turns out “science” is a key aspect of why coco coir is an ideal medium for growing cannabis as well as other crops. Some of the properties of coir that allow crops to thrive when grown in it include:

Neutral pH. Its pH is close to neutral (6), so coir can be used straightaway. Peat is acidic (as low as 3-4) and needs to be treated with lime before use. This neutrality is good because it allows the user to add the nutrient mix of their choosing.

High cation exchange rate. This allows nutrients to be stored and used as needed, except for calcium and magnesium, which coir tends to hold on to. Adjust your nutrients accordingly. A calcium and/or magnesium supplement is a must do when growing in coco coir.

Packed with nutrients and biostimulants. It’s a formerly living thing, so it comes packed with its own set of nutrients, such as potassium, iron, manganese and zinc, to name a few. Again, you should take this into account when considering what nutrients to apply. It also contains biostimulants, which act as growth enhancers and give whatever is planted in it a boost.

Watch for salts. If there is a downside of coir it’s the fact that the product in its raw form contains salts. You, the end user buying coco coir products, don’t really need to worry too much about the salt level because it has been processed and washed extensively before you receive it. But if for some reason you’ve found some compressed blocks of raw coir, do know the salts need to be rinsed away or else it can harm your crops.

What Makes Cocodelphia Great

We at Organic Mechanics think our Cocodelphia coco coir product is one of the best on the market. Why? For one thing, we buy our coir from just one farm in India, so our variability in quality is essentially non-existent. That farm washes the coir several times and relies on the monsoons of Southeast Asia to accomplish this. Once we have received the coir, it’s washed again as we rehydrate the air-dried, compressed coir blocks. Essentially, Cocodelphia is triple washed.

Our Cocodelphia is also continually tested for heavy metals, and each test result comes back clean. Don’t just take our word for it! Our customers have done their own testing and tell us it’s the cleanest heavy metal-free coir for cannabis production around. And for you professional cannabis growers out there, you know cannabis that fails a heavy metal test means a lost crop and lost profits.

Cocodelphia is also ready to go straight out of the bag. Add in some other beneficial amendments such as Biochar Blend or Worm Castings for a punch of nutrition. Or plant in the bag and save yourself the time of potting.

For more information about coco coir, check out the great content on the Maximum Yield site, beginning with THIS ARTICLE.

Do Note! Cannabis production is not legal nationwide. While it may be legal to cultivate cannabis where you are, many states do still consider it illegal unless you possess a state-issued license. Check and abide by your state and local laws before you grow. If, however, you have the option to grow cannabis and you know you are doing everything legally, by all means, please do! And give our Cocodelphia a try while you’re at it.

How Do I Germinate Cannabis Seeds and Transplant Clones?

Clones and seedlings may seem very similar, but there are some differences between the two starting points. First of all, seedlings (small plants sprouted from seed) have a taproot. This is a central dominant root that tends to grow straight down and proliferate the branching root structures that explore the growing medium. Clones do not have a taproot; instead, they immediately begin producing a fibrous branching root structure. I would argue that the taproot is most important in outdoor grows due to the higher degree of anchoring and stem support that it can provide in windy weather.

Secondly, seeds all have unique genotypes while clones have the same genotype as the mother plant they were cut from. Truly stable seed lines produce plants with phenotypes so similar that they could be mistaken for clones, but usually in the Cannabis industry, a given seed pack for a strain may produce multiple different phenotypes. Sometimes this can be desirable if you are phenotype hunting for a unique plant to grow or breed with, but at least in large scale production, uniformity is usually preferred because it simplifies the growing, harvesting, and processing techniques

How Do I Germinate Seeds?

There are many ways to skin this particular cat. First of all, it is important to consider the environmental conditions required for germination.

While some small seeds without much of a starch reserve require light to germinate, it appears that light actually inhibits the germination of Cannabis seeds. This is likely due to the red light sensing system by light-sensing proteins called phytochromes. In general, far-red light can penetrate further into soil than red light due to the longer wavelength. Plants often utilize the ratio of far red light to red light as a way to sense depth in soil. For Cannabis, it appears that it requires a low far red/red ratio (no to minimal light) in order to germinate. However, pure darkness is unnecessary in my experience. In fact, it is a bit of a balancing act because after germination, your seedlings require light or they will not begin to produce chlorophyll and will continue to etiolate (grow and stretch in search of light to begin photosynthesis). Therefore, you will need to check your seedlings frequently so if you germinate in complete darkness, you can quickly introduce your newly sprouted seedlings to light.

Moisture and Humidity

Seedlings require water uptake in order to trigger germination. The media they are in contact with should be moist, and the humidity should be kept high but ventilated to help prevent microbial growth. In general, this translates to around 70-90% humidity. However, I don’t generally keep track of the humidity of the air in my germination area. Humidity is ensured to be high by enclosing the germination medium with a ziploc bag with holes cut in it.

I like to follow the rule of thumb: keep the temp in the 70s throughout the day and night. Don’t let temperatures dip below 70F and don’t let temperatures rise above 80F. In Celsius, this translates to approximately 21-27C. In practice, it is okay if it gets warmer, though I certainly would avoid letting temperatures get above 30C (86F). However, high heat can inhibit germination and encourage microbial growth. Also, dipping below 70F does not ensure failure, but may not be as efficient at germinating seeds.

I will only cover 2 germination methods. This is because in my opinion, they are simple, effective, and I have experience in both.

Method 1: Wet Paper Towel.

Get a paper towel and soak it in water (it is probably ideal if you get sterile, deionized water, though I generally use tap water and it works just fine). Squeeze out the paper towel so that it is damp but not wet. Place your seeds on the damp paper towel, and fold the paper towel one time over the seed. Place the folded paper towel in a gallon size plastic bag.

Option 1: Poke a few holes in the plastic bag (I like to use sharpened pencils, it has a good size for holes), blow into the bag to ensure it’s not collapsed on the paper towel, seal the bag, and place it in a dark, warm place. Check daily for germination and make sure to keep the paper towel moist. If it gets too dry, just use a spray bottle to spritz the inside of the bag and paper towel.

Option 2: Don’t poke any holes, exchange the air inside by sucking the air out the bag and blowing back into it to inflate it. Seal the bag, place it in a cool, dark place, and exchange the air in the bag once to twice/day and check frequently for germination.

Transplanting Germinated Seeds

After germination, I like to wait until the taproot is about an inch long. After this, pick it up by the seed coat with tweezers or a very gentle touch. Don’t touch the taproot. take your soil or growing medium, moisten it using appropriately pH’d water (around 6.5 for soil) and prepare a a hole deep enough to place the germinated seed in with the taproot facing down and the seed coat barely below the soil line. Place the seed in so that the taproot is straight down and so that the tip of the taproot is not bent or hooked when you plant it.

Method 2:

Plant your seed directly in a seed starter (I like to use coco coir with a bit of mycorrhizal fungi sprinkled in).

Option 1 is to buy seed starter coco coir pellets. All that is required is to wet the pellets with properly pH’d sterile water. They will expand and will have a small hole in the center for you to place your seed. After planting your seed, gently cover it up. This will provide both light and local humidity around your seed. Cover the pellet loosely with an open plastic bag to help retain moisture and leave it on a windowsill or under artificial light. This will ensure that once the seed germinates under the soil which is dark and humid, it will sprout above the ‘soil’ line, remain in a humid environment in the plastic bag , and will also be exposed to light so that the seedling can begin photosynthesis. I do not like to use peat moss or peat-based pellets such as Jiffy pellets. First of all, coco coir is far more environmentally friendly because peat is a nonrenewable resource, unlike coco coir. I stay away from rock wool for the same reason, coco coir is just a more responsible consumer choice for the environment. Secondly, peat is extremely acidic and may affect nutrient uptake early in a plant’s life as compared to coco coir. For all seed starting mixes, I like to make about a quarter of the volume perlite. Seedlings do not uptake water well and you want good soil aeration to avoid damping off and root rot diseases. If you use premade pellets, you will not have this option.

Option 2 is to fill a small, 2-3 oz plastic cup with coco coir, moisten it and make a hole for the seed yourself, and sow your seed. Follow the same directions as outlined for the pellets.

What do I do now that my seedling has germinated?

Now that you have a germinated seedling, you will notice two small ‘leaves’ that are kind of oval-shaped. These are known as cotyledons, and can actually help provide your plant with nutrients that were stored in the seed until the plant can feed on fertilizer or nutrients in soil depending on your growing style.

You will want to provide your plant with enough light to not stretch out. You can get away with using even a 60W single CFL ‘grow’ bulb for a seedling, but I tent to keep my seedlings under a 300W LED panel. I like to keep the light source about a foot from the top of my seedling.

Go ahead and keep the temperatures in the 70s (Farenheit). This is a great range for Cannabis growth and isn’t as conducive to disease development as warmer temperatures.

You will want to slowly lower the relative humidity. Keeping the same level of humidity as for germination will prove to be too conducive to disease development especially seedling damping off and root rots. Go ahead and keep the plastic bag over the seedling at first, and slowly increase the amount of time each day that it is not under the plastic bag. In general, I like to leave the bag off the seedling at night after it sprouts and during the day, reduce the time it is under the bag by an hour each day until the second set of true leaves are visible, then remove it altogether.

Seedlings require more moisture that mature plants but you also want to avoid root rots. Therefore, I like to use a spray bottle to mist the soil every day without soaking it. This should be done until the second set of true leaves are visible, then begin your normal watering schedule. Your seed starter mix should not have fertilizer in it. Your plant should have all the nutrients it needs from the cotyledons and all the energy it needs from photosynthesis. However, after the first true leaves are fairly large and the second set of true leaves are barely visible, I will sometimes include a Nitrogen dominant fertilizer at 1/4 strength in the spray bottle and lightly mist until slightly damp (I only ever do this once before transplanting, and only if the leaves are looking light). I tend to use liquid fertilizers (you can find conventional or organic fertilizers depending on your fancy).

Transplanting Your Seedling

By the time the second set of true leaves have grown in, your seed starter plug should be colonized by roots. Or, if you purchased a clone, it is likely already rooted in a rock wool cube. Take a pot approximately 10x the volume of your rooting medium, fill it with the planting medium of your choice (soil or soilless medium[if soilless, it is a good idea to do a light feeding (1/4 strength) as well at this point]). Water the medium in your new pot before transplanting and allow it to drain to field capacity. Make a crater in the center of your moistened medium deep enough to completely cover the seedling medium. I like the lowest nodes on the plant to be about 1-2″ above the soil line after planting. Place in your rooting plant, fill in the crater, smooth it out, and lightly pack in the planting medium around the stem of your plant. Water the pot once more to ensure the soil settles in, allow it to drain capacity.

Congratulations, you have germinated your seed and/or transplanted your clone/seedling. That was pretty easy, right?