Cornmeal gluten, commonly referred to as corn gluten meal (CGM), is the by-product of corn wet milling. It is used to feed cattle, fish, dogs, and poultry. Gluten meal is known as a natural substitute for chemical pre-emergent herbicides. Using this cornmeal as weed killer is a great way to eradicate weeds without the threat of toxic chemicals. If you have pets or small children, gluten meal is a great option.
It is important to note that cornmeal gluten is only effective against seeds , not plants that are mature, and is most effective with corn gluten having at least 60% proteins in it. For annual weeds that are growing, plain cornmeal products will not kill it . These weeds include:
Be sure to follow the application instructions on the package and apply before weeds start to grow . Sometimes this can be a very tight window, but is best done in early spring. In flower and vegetable beds where seeds are sown, be sure to wait to apply at least until the seeds are grown up a bit. If applied too early, it can prevent these seeds from sprouting.
Gluten Cornmeal as Weed Killer.
However, cornmeal gluten will stop the seeds that these weeds shed in the summer so that the weeds will not increase. With consistent use of gluten meal products, these weeds will gradually decline.
Many people use corn gluten on their lawns, but it can be safely and effectively used in gardens as well. Using gluten cornmeal in gardens is a great way to keep weed seeds from sprouting and will not damage existing plants, shrubs, or trees.
Researchers at Iowa State University discovered by accident that cornmeal gluten acts as an herbicide while they were doing disease research. They saw that corn gluten meal kept grass and other seeds, such as crabgrass, dandelions, and chickweed from sprouting.
Cornmeal gluten is also a popular method to control ants. Pouring it wherever you see ants traveling is the best option. They will pick up the gluten and take it to the nest where they will feed on it. Since the ants cannot digest this cornmeal product, they will starve to death. It may take up to a week or so before you see your ant population dwindling.
Perennial weeds will not be damaged either. They pop back up year after year because their roots survive under the soil over winter. Some of these include:
Tip : If you have large areas to cover, you can try a spray form for ease of application. Apply every four weeks, or after heavy rains, during the growing season to maintain effectiveness.
How to Use Cornmeal Gluten in the Garden.
Using Cornmeal Gluten to Kill Ants.
Corn gluten meal is found in both pellets and powdered forms. The application process involves spreading it in a specific amount that is based upon how many square feet of ground needs to be covered.
Even if you choose to experiment with corn gluten meal, you can still expect to need post-emergent weed spraying. This method gets rid of weeds that are already visible above the ground that the meal cannot kill.
Pre-emergent sprays work similarly to corn gluten meal by suppressing weed growth at the seed level, but it is a little different. A pre-emergent spray prevents seed germination. The seeds never develop roots or sprouts.
How Do People Use Cornmeal as a Weed Killer?
Weeds grow throughout the year in Arizona. Even annual weeds may occasionally pop up before you expect them in the spring. Once they do, this method is not effective at all. It also requires frequent reapplications. Keeping up with this method can be frustrating for busy property owners.
There have been multiple studies on the use of corn gluten meal as an effective weed killer with mixed results. The primary issue with this method is the difficulty of applying it at just the right time to knock out the weed seeds.
The biggest mistake that most people take with this natural weed remedy is running out to buy cornmeal from the grocery store shelves. The type of cornmeal that you eat is not the same as what you need for weed killing purposes.
This method only works on weeds that have not sprouted yet. People often use it on annual weeds such as purslane. Keep in mind that it will not work on perennial weeds that have already established a root system.
Cornmeal is the latest natural weed killer that has been making the rounds on social media. The prospect of being able to kill weeds with a simple sprinkle of cornmeal is exciting. Most people find cornmeal to be cheap and readily available, but the real question is does it work?
Since corn gluten meal has high levels of protein, nitrogen, and oils, it is also used for lawn fertilization and weed control purposes. It is sold in lawn and gardening stores rather than at your local grocery store.
The cornmeal in your pantry is made from ground-up corn kernels. This is what you use as an ingredient in recipes for cornbread and other dishes.
How Effective Is It?
The quest for the perfect weed killer has led to some interesting preparations. You’ll find natural remedies that range from using boiling water to vinegar and soap. While many of these remedies work, they tend to be difficult to implement on an entire batch of weeds. They also have only short term effects.
After the meal is distributed evenly on the ground, you then need to water the lawn lightly to activate the oils. If the application does work, it is only effective for around 5 to 6 weeks. Then, the meal must be reapplied.
So what’s the verdict? Corn gluten meal may help with preventing weeds from emerging from your lawn. This only works if you are diligent about following the proper application process and okay with it not always working.
Corn gluten meal is a byproduct that is created during the wet milling process of making cornmeal. It is not meant for humans to eat, but it is sometimes used in pets and cattle feed.
There are also more effective methods for getting rid of those unsightly plants. Proper weed control involves a careful plan that addresses the types of weeds that appear in your lawn at every stage of growth.
Does It Work on All Weeds?
Help Desk Response: Thank you for contacting the UC Master Gardener Program Help Desk with your question about cornmeal and weeds. I am going to assume that you mean corn meal gluten (CGM), a by-product of corn starch manufacturing that is marketed to home gardeners for pre-emergent control of weeds, especially in lawns. Yellow corn meal makes great polenta, but won’t do much for weeds!
Better weed control can be achieved by heavily mulching the area, which will prevent weed seeds from sprouting. At this time of the year, late winter, when many of our weeds have already come up, you can try hand-pulling or hoeing out the small weeds. They are always easiest to control when they are small. This link will give you great information from UC about weed management in the landscape: http://ipm.ucanr.edu/PMG/PESTNOTES/pn7441.html. The key to successfully reducing the weed problem in future years is to make sure none of this year’s weeds go to seed.
CGM will have no effect on already-emerged weeds; it only suppresses some seeds’ ability to sprout. It is sometimes used though where only organic herbicides are permitted, but its effectiveness is still questionable. It should not have adverse effects on soil. Because it is high in nitrogen, it could be beneficial if your soil is deficient in that nutrient.
University of California research has not shown CGM to be an effective weed control strategy, but in a lawn, it may work because it is high in nitrogen and will feed the lawn, making it more dense, and likely crowding out weeds. Lawns already fed with high nitrogen fertilizers probably won’t show any significant benefit from CGM.
Client’s Request: I’ve heard that I can use yellow corn meal to control weeds. Is this doable and will it hurt the soil?
Advice for the Home Gardener from the Help Desk of the UC Master Gardener Program of Contra Costa County.
Weeds in our gardens are frustrating and seem to be extra-abundant this year because of all the rain we’ve had. Good luck!