Does cornmeal kill weeds? The answer to this question might surprise you. Cornmeal might be an interesting weed preventative. Using Cornmeal Gluten In The Garden Corn gluten meal is sold as an organic pre-emergent weed control alternative to synthetic chemicals. Success relies on timing.
Garden Myths & Facts: Does Cornmeal Kill Weeds?
As more and more people are becoming environmentally conscious due to the insane devastation wreaked on the natural world with toxic herbicides, many are looking for natural alternatives for their gardens. This has led many people to wonder – does cornmeal kill weeds?
The origins of this idea are interesting, but the factual evidence doesn’t always line up. In this article, we’re going to explain whether or not cornmeal can be used to kill weeds.
Why Would Cornmeal Kill Weeds?
Cornmeal – or rather, cornmeal gluten – is an agricultural byproduct. It’s the leftover material from the corn milling process.
For the most part, cornmeal gluten is used to feed animals. However, cornmeal gluten has also gained a reputation for being useful as a pre-emergent herbicide.
One of the biggest selling points is that cornmeal is non-toxic, which makes it an appealing alternative for toxic herbicide products.
Another interesting thing to note is that cornmeal is filled with protein and nitrogen, which can make it a useful fertilizer for your lawn. But wait – wouldn’t that make it healthy for weeds?
Does Cornmeal Kill Weeds or Not?
There is some debate as to whether or not cornmeal will actually kill weeds. The shortest answer is that, no, it will not kill living weeds.
One of the original reasons that people thought this was because of a misinterpreted story from Texas A&M. While the ‘research’ didn’t actually conclude that cornmeal killed weeds, people misinterpreted the data and came to this conclusion.
The rumor was then further developed to suggest that cornmeal contained ‘beneficial organisms,’ which could help out a lawn or a garden. This simply isn’t true, and cornmeal doesn’t contain any organisms except for perhaps microbes that could be growing on it.
However, cornmeal can still be useful to help prevent weeds. It is known to work as an effective pre-emergent herbicide. The reason for this is because corn meal has an oily coating that prevents plant roots from forming.
This means that cornmeal gluten can be useful for preventing weeds, but only if it’s applied in the right way at the right time.
Applying Corn Gluten Meal
You need to make sure that you are using corn gluten meal, not regular corn gluten.
You will need to use about 20 pounds of corn gluten meal per 1,000 yards of lawn. After you have distributed the corn gluten meal, then water the lawn. This will help to activate the corn gluten meal and prevent your weeds from taking root.
It’s also important to apply the corn gluten meal at the right time. That means before the weeds take root. For most normal weeds, which sprout in spring and summer, you can use your corn gluten meal in early spring.
Corn gluten meal – which is different from cornmeal – can be used to help prevent weeds from taking root. It’s not an effective post-emergent weed killer, but it can certainly be a useful tool for anyone who is hoping to prevent springtime weeds without relying on toxic chemicals.
Does Cornmeal Stop Weed Seeds From Germinating
Using Cornmeal Gluten In The Garden
Is this something you have tried? We would love to hear your successes and failure along with other suggestions for organic weed and pest control, so we can share the knowledge. Corn gluten meal (CGM), is the by-product of corn wet milling. It is mainly used to feed cattle, fish, dogs, and poultry and as a food source in some less developed areas of the world. Accidental research has found that Gluten meal is a natural substitute for chemical pre-emergent herbicides, which means it can stops weeds from germinating. There appears to be lots of evidence that shows through using this cornmeal, results in a fantastic weed killer or weed preventer. Showing that it is a great way to eradicate weeds without the threat of toxic chemicals something that we are all for here at Friendly Organics. If you have pets or small children or prefer the more natural route, gluten meal is a much safer option.
As I mentioned the weed killing attributes were discovered by accident through research carried out by Iowa State University, they were actually looking into disease research but observed that cornmeal gluten acts as an herbicide as it kept grass and other seeds, such as crabgrass, dandelions and chickweed, from sprouting.
However, 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 but it will help prevent their spread via seeds.
Perennial weeds will not be damaged either as their roots survive and they return each year, as mentioned cornmeal will stop their seeds becoming further plants so reducing the weeding you have to carry out. With consistent use of gluten meal products, these weeds will gradually decline and eventually you should have a weed free garden.
The use of cornmeal gluten can be extended to the lawn element of your garden as grass is a well established plant and should not be effected.. Using gluten cornmeal in gardens is a great way to keep weed seeds from sprouting and will not damage existing plants, shrubs or trees. 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. Be sure to wait to apply in flower and vegetable beds where seeds are sown at least until the seeds are grown up a bit. If applied too early, it can prevent these seeds from sprouting. Using Cornmeal Gluten to Kill Ants 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. Because 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.
Corn Gluten: An Organic Pre-Emergent Herbicide
Kelly Burke is a professional turf manager for a manicured corporate campus in New England. He is accredited in organic land care and is a licensed pesticide applicator. He formerly managed the turfgrass as a golf course superintendent and has held several senior management positions at private country clubs overseeing high maintenance lawns.
Kathleen Miller is a highly-regarded Master Gardener and Horticulturist who shares her knowledge of sustainable living, organic gardening, farming, and landscape design. She founded Gaia’s Farm and Gardens, a working sustainable permaculture farm, and writes for Gaia Grows, a local newspaper column. She has over 30 years of experience in gardening and sustainable farming.
Emily Estep is a plant biologist and fact-checker focused on environmental sciences. She received a Bachelor of Arts in Journalism and a Master of Science in Plant Biology from Ohio University. Emily has been a proofreader and editor at a variety of online media outlets over the past decade.
Corn gluten meal is a powdery byproduct of the corn milling process. Originally used as a supplement in hog feed, corn gluten has become a common organic alternative to synthetic chemical herbicides. It can be effective as a pre-emergent herbicide used to control crabgrass and other lawn weeds, and it also has nutritional properties. Corn gluten meal is about 10 percent nitrogen by weight, meaning 100 pounds of corn gluten contains 10 pounds of nitrogen. This organic source of nitrogen is slowly released over a three- to four-month period.
How Corn Gluten Works
Corn gluten does not prevent weed seeds from germinating, but it does inhibit those seeds from forming roots after germination. This means that applications must be very carefully timed. When the application of corn gluten is timed correctly, crabgrass seeds germinating will form shoots but not roots, and will therefore die, provided there is a short dry period after seed germination. However, if conditions are too wet immediately after seed germination, the weed can recover and establish a root.
Corn gluten is useful only as a pre-emergent herbicide; it provides no post-emergent weed control. If crabgrass and other weed seeds have already germinated and taken root, a late application of corn gluten will only serve as fertilizer for the weeds. Further, applications of corn gluten need to be precisely timed around rainfall or watering. After application, corn gluten needs to be watered in, either by rainfall or by artificial watering, within five days of application. Rainfall of about 1/4 inch, or a comparable artificial watering, is ideal. After this, a dry period of one or two days is required to prevent weed seedlings that have germinated from growing roots.
In other words, corn gluten needs water just after application, but a dry period is then required in order for germinated weed seeds to have their root production inhibited. It can be quite difficult to get this application timing precisely correct.
The first application of corn gluten won’t suppress all of the weed seeds, and a single application may help suppress weeds for four to six weeks. Heavy soils, extended rainy weather, and hot spells may require a monthly application or a second application in late summer. The initial results may be disappointing but after several applications, corn gluten sometimes reaches 80 percent effectiveness at controlling crabgrass.
How Much Is Needed?
Application rates vary by form: powder, pelletized or granulated. The standard application rate is 20 pounds of corn gluten per 1,000 square feet of lawn. This rate also provides about 2 pounds of nitrogen per 1,000 square feet.
The effects of corn gluten are cumulative, meaning that the results improve with repeated use over time.
Some experts are critical of using corn gluten as a pre-emergent crab-grass killer, pointing to several points:
- Corn gluten is costlier than conventional pre-emergent herbicides. Because multiple applications are often required, you could be handling hundreds or even thousands of pounds of the product, depending on the size of the yard. Sprayable, liquid forms of corn gluten can make applications easier, but they are still costly.
- Timing is critical for both organic and synthetic chemical pre-emergents. It’s very important to remember that all pre-emergents, including corn gluten, will suppress all seeds, including grass and flower seeds. If you are using non-selective pre-emergents in the spring and summer, any lawn seeding should be done in the fall.
A synthetic chemical pre-emergent is a non-organic herbicide that is applied to the landscape prior to weeds and other unwanted plants growing. In essence, it prevents those plants from emerging from the soil where seeds might lie.
- The nitrogen in corn gluten has drawbacks. Some turf specialists argue that extra nitrogen only gives weeds the advantage.
- Encouraging new grass is more effective. Crabgrass is a filler weed that thrives in bare spots or areas with thin turf grass, and organic turf specialists contend that seeding with new grass is just as effective as applying pre-emergent herbicides such as corn gluten. Dense, healthy turf will naturally crowd out crabgrass, so growing more grass and filling in those thin areas and bare patches may be a better solution.
Corn gluten does work as a pre-emergent herbicide, through a mechanism that inhibits germinated weed seeds from establishing roots. But timing the applications correctly is tricky, and it may require repeated applications in order to really see the desired results. Further, corn gluten can also inhibit new turf grass seeds from becoming established.
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