Biological control is the deliberate introduction of insects, mammals, or other organisms which adversely affect the target weed species. Biological control is generally most effective when used in conjunction with other control techniques.
- The ragwort flea beetles (Longitarsus jacobaeae) mine the roots of the rosettes and kill plants in the spring when they start to bolt. Flea beetles are most effective in sunny pastures that do not flood and are below 2400 feet in elevation.
- Biological control can take up to six years to have a significant impact. Population density and the number of flowering plants can be reduced, but there will always be some plants remaining. Therefore, any biological control plan needs to incorporate another non-chemical control method to be able to prevent all seed production.
- Biological control is not recommended for small infestations.
- Only apply herbicides at proper rates and for the site conditions or land usage specified on the label. Follow all label directions and wear recommended personal protective equipment (PPE).
- Monitor treatment areas for missed and newly-germinated plants.
- Choose selective herbicides over non-selective herbicides when applying in a grassy area.
- Minimize the impacts to bees and other pollinators by controlling weeds before they flower. When possible make herbicide applications in the morning or evening when bees are least active. Avoid spraying pollinators directly.
Specific Herbicide Information
Herbicides are described here by the active ingredient. Many commercial formulations are available containing specific active ingredients. References to product names are for example only. Directions for use may vary between brands.
- Apply selective herbicides in the spring before any flowers appear. Fall applications after rains have initiated seed germination can also be effective. Check label for specific information on rain guidelines.
- Selective herbicides that are effective on tansy ragwort include 2,4-D, dicamba or a combination (e.g. Weedmaster, Weed-B-Gon).
- Spot spraying with glyphosate (Roundup) can effectively control tansy ragwort. Treatment with glyphosate may need to be combined with effective re-vegetation of the site to prevent tansy ragwort seedlings from re-infesting the area.
- Re-treatment is necessary to control late-germinating plants. Monitor for new plants for at least four years after the initial treatment and following any disturbance to the soil such as tilling or construction.
- Both dicamba and 2,4-D can harm certain grasses, alfalfa, clover, and other legumes. Please refer to the label.
This BMP does not constitute a formal recommendation. When using herbicides, always consult the label. Please refer to the Pacific Northwest Weed Management Handbook or contact your local weed authority.
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My Garden Is Planted, How Do I Manage Flower Bed Weed Control?
When you finish the time-consuming, back-breaking labor of planting your garden, flower bed weed control is the last thing on your mind. But the harsh reality is that in practically no time, you will be facing the last thing you want to see in your flower bed – weeds!
Weeds pop up despite most gardeners’ best efforts, and they grow fast. In fact, some weeds grow much faster than the flowers. This means they will eventually choke out the sunlight and pull nutrients away from your plants. This effectively destroys your garden.
As the gardener in charge of your flower bed, it is your job to get them under control. However, that’s not an easy task. We have sought out the best flower bed weed control tips to help. Follow these steps to ensure the best possible weed control for your flower bed:
Step #1: Block Out the Sun
Like all plants, weeds need sunlight to thrive. So depriving them of it is a great way to kill off weeds and deter new growth. To implement one of the most effective strategies for weed control in your garden, lay a 2-inch thick layer of dark mulch in the area around your flowers. Ensure there is no space between plants left unprotected by mulch. This dark layer will prevent the sunlight from getting through and feeding those weeds you don’t want to grow.
Step #2: Don’t Water Weeds
It is important to water your flowers to keep them healthy and growing. However, it is equally important not to water weeds. Instead of watering a large area of your garden, be strategic in watering. You should only water the areas with your flowers and not areas that could have weed seeds. Soaker hoses or drip irrigation can help you to water more effectively. There is an abundance of weed seeds in the soil. And, when they get water, they are likely to start growing. Depriving them of water will impede their development.
Step #3: Pull Out Those Babies
Young weeds that are just starting to grow are the easiest to eradicate. Make a point of regularly weeding your flower garden and pulling those weeds that are new growth. Lay them out on concrete or your driveway and let the sun kill them before disposing of them. Remember never to place the dead weeds in compost. Some seeds might still be lingering, and the last thing you want is compost full of dormant seeds just waiting for a chance to grow.
Manually weeding a garden is the tried and true method of ridding it of weeds without damaging the other plants and flowers. When you consistently spend the time pulling them out by hand, you can target young weeds for the best results possible.
Step #4: Cut Off Their Heads
If the weeds in your garden are too hard to remove, make an effort to cut off their tops at least weekly. By taking the time to do this, you will prevent the plant from going to seed and spreading that seed throughout your yard. It may not get rid of the current weeds. However, it will prevent the problem from worsening. Another tip is to avoid soil disruption as much as possible to avoid triggering the growth of weed seeds that are dormant in the soil of your yard.
Step #5: Use Herbicide Sparingly
Even though it is not ideal, you can use certain herbicides on weeds found in your flower garden. Before doing this, make sure you know what type of weed you are dealing with. It is important to get the right type of herbicide to take care of it. Be sure it is not dangerous to your flowers. Apply it sparingly only to the areas where weeds are a problem. Note: this is a strategy often best left to professionals. Your lawn care service can effectively rid your flower bed of annoying weeds and treat it to prevent new ones from popping up.
Weed Control by Think Green Lawn Service
Weeding is one of the most dreaded chores faced by gardeners everywhere. There’s nothing more irritating than admiring your carefully planned garden and then seeing weeds mar the perfection. By using these guidelines, you are much more likely to get them under control for a better-looking garden week after week, all summer long.
To get more information about flower bed weed control or to schedule a visit from one of our professionals, contact our friendly team of experts at Think Green Lawn Service today. Our experienced technicians will be happy to help you come up with the perfect solution for a weed-free lawn you can enjoy.