Looking for a natural weed killer? You’re in luck, we know of one that works great that you’ve probably never heard of. Yes, it’s natural and it kills weeds!
In today’s world, most of us are trying to avoid chemicals as much as we can. One of the ones that you can avoid completely, is a pre-emergent weed killer. I’ll show you how this is possible using an ingredient you probably already have.
What is a Pre-emergent Weed Killer?
Weeds usually start out as seeds. This method works very well for them, but will not work on weeds that rely on runners, roots or bulbs to reproduce. There are other methods for those. A pre-emergent weed killer stops the weed seeds as they germinate, so they will not produce plants. I got my first dose of this about 25 years ago when I was taking care of my grandmother’s lawn. It looked great, then all the dandelion seeds rooted and they were everywhere! (of course, now we know dandelions are a valuable herbal resource!) I used a chemical pre-emergent that worked well and didn’t allow the seeds to take root after that. But I knew there had to be a way to control the weeds without chemicals.
Corn Gluten is a Natural Weed Killer
In doing some research, which in those days meant running around to garden centers since the internet wasn’t really in use yet, I found a product called Preen®. It promised to kill the weeds before they came up and work for a few months. Ok, it worked, but it was still a chemical. It contains Trifluralin. While considered a low-risk product, it still has warnings and it’s still a chemical. Was there something more natural? Yes! Preen® also makes an organic product, which contains corn gluten meal. What does it do? Exactly the same thing! It won’t last as long in your garden, but it’s non-toxic and safe around kids and pets.
Corn gluten meal is available from a number of companies and is relatively inexpensive. We recommend using Dave Thompson’s Organic Healthy Grow Corn Gluten. We did the research for you but if you want to do more reading on the efficacy of corn gluten as a natural weed killer, read the clinical trials here.
How to Use Corn Gluten as a Natural Weed Killer
To use it, you need to be sure that any seeds that you DO want to sprout are already up. It won’t harm existing plants. Next, it’s best to have bare soil, but it can work on grassy areas such as lawns. The dandelions weren’t the only things I wanted to get rid of, crabgrass is another. Once that stuff takes root, you need a backhoe to get rid of it! Ok, not really, but it seems like it. It’s really tough to get out of flower beds, so keeping it out is key.
Here’s the hard part: crabgrass has a very short window of germination. It usually occurs in the early spring right after the first bout of very warm weather. Here in Western North Carolina that can be as early as January and as late as April. The germination period only lasts a few weeks, so if you don’t catch it in time, you’ll have crabgrass sprouting. Hence the claims that this product doesn’t work. Corn gluten as a natural weed killer does work, you just need to apply it at the right time.
How I Use Corn Gluten
Each spring I get my garden planted, then I sprinkle the corn gluten meal on the soil. You don’t need to water it in or distribute it into the soil. It’ll take care of itself. If you can’t find corn gluten meal where you live, it’s available on the internet. Oh wait, you probably have some in your pantry and didn’t even realize it. Plain old cornmeal will work just as well. Yep, cornmeal. It doesn’t matter if it’s white or yellow, or even blue or red, it all works the same way. Grits are made from corn too, but they don’t seem to work as well. I’m not sure exactly why as it would seem that they are about the same thing.
Tips on Weed Germination
It helps to remember that weed seeds have a certain germination period. Some, like crabgrass, have a short window in the spring, while some, like the dandelion, can shed seeds all summer. knowing when things flower and produce seeds is a big help. There is a lot of information online about plants and when they produce. If you need help with local plants, try your local Master Gardener. They’re a part of your local county extension office (here in the US) and they can be a huge help. I was a part of the Master Gardener program for many years and identifying weeds and using natural weed killer were some of the things I helped people with.
Life Span of Corn Gluten
Remember also that corn gluten meal has a short life span. It usually lasts about six weeks. If you want to plant seeds in the same spot later, it’s best to wait three months to be sure all of it has been expended in the soil. Corn gluten meal will also slowly release nitrogen into the soil over 3-4 months. A nice added bonus!
Another good thing to remember is that it won’t take care of existing weeds. Once they sprout, you’ll need to get rid of them another way, like our homemade weed killer.
Tips for Using Corn Gluten as A Natural Weed Killer
One of the only drawbacks that I’ve seen with the corn gluten meal is that it can attract rodents. If you fear voles and mice in your garden, place some of the meal in a coffee can and add some powdered cayenne pepper. That will usually do the trick! And if the meal stays on the surface and gets moldy, which can happen in damp climates, just sprinkle some cinnamon on top of it. That will usually take care of any mold.
Have you tried corn gluten meal for weeds? Tell us what you think!
FAQs
Like most natural herbicides and pesticides, corn gluten meal works slowly and is a long-term treatment. The second application can result in a 70% – 80% reduction in the weed population, and if used repeatedly for 2 or 3 years, it can eliminate over 90% of the weeds in your lawn and garden.
How to use corn gluten meal to kill weeds? ›
Spread it evenly over the lawn at a rate of 20 pounds per 1,000 square feet and water it lightly into the soil. After watering, let the soil dry out somewhat so that the sprouted weed seedlings dry up and die. CGM can also be applied in mid-August to control late-season annual weeds.
Can you use cornmeal to kill weeds? ›
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.
Can you put too much corn gluten on your lawn? ›
Too Much of a Good Thing
Some is helpful, but too much can spoil the job. Corn Gluten Meal needs to be watered in within 5 days of application.
Will corn gluten kill new grass seed? ›
Note that corn gluten will, also, suppress the germination of turf grass seeds, so either plant these seeds in locations away from corn gluten application or wait four to six weeks after for its herbicidal effects to wear off.
Is corn gluten meal safe for dogs? ›
However, Case explains it isn't “a 'complete' or high-quality protein source for dogs (or humans) because it is deficient in several essential amino acids, such as lysine, arginine, and tryptophan.” So corn gluten meal needs to be balanced with other protein sources to ensure your dog gets these essential nutrients.
What is the best homemade recipe for killing weeds? ›
To make a homemade weed killer using the three ingredients mentioned: Mix 1 gallon of white vinegar and 1 cup of salt until the salt dissolves. Add 1 tablespoon of washing up liquid to the mixture and stir well. Add the mixture into a spray bottle.
What is the best thing to kill weeds forever? ›
Strong horticultural vinegar works best, because vinegar from the grocery store is not strong enough. When applying horticultural vinegar, be mindful of nearby plants, so you don't accidentally overspray and kill a desired plant. Learn when annual weeds set seed and target them before they produce a new generation.
What is the difference between cornmeal and corn gluten meal? ›
Cornmeal is simply ground corn that we use in cooking. It is an essential ingredient in cornbread and corn muffins. Although it might add some nutrients when sprinkled on the garden, it likely does not have any effect on weeds. Corn gluten meal (CGM), on the other hand, is an industrial by-product of grain wet-milling.
Does corn gluten prevent dandelions? ›
Corn gluten prevents the germination of dandelion and large crabgrass seeds by releasing amino/dipeptides (proteins) into the soil, starving the roots of water. Apply when the soil is moist and when rain is forecasted within 2 days of application.
Corn gluten meal needs to be watered in to activate. Ensure about ¼ inch of water using a garden hose with nozzles or the sprinkler system.
Does corn gluten prevent clover? ›
Corn gluten is a by-product of the wet milling process used to produce corn starch and corn syrup from corn. As you can see, it's a natural product and contains around 10 percent nitrogen. It is the large amount of nitrogen clover dislikes and will turn up it's toes as a consequence.
Does cornmeal stop weeds from growing? ›
Sprinkling corn meal around your garden will attract ants, slugs and probably snails but it won't stop weed seeds from germinating.
Will earthworms eat cornmeal? ›
But food waste and paper waste often do not provide enough protein to get fat, chubby worms. Fat worms are important to bait sellers as well, so in order to add a little meat to their, uh, “bones,” you can supplement with a protein-rich mix of cornmeal, chicken mash, alfalfa, kelp meal, soybean hulls, and more.
What does cornmeal do for grass? ›
Corn meal can be used for three different purposes--fungal control, soil conditioning, or feeding your lawn. This is the same corn meal available at any grocery store, although it tends to be much less expensive at a feed store or grain mill.
Will corn gluten meal kill clover? ›
While they won't do anything to already established clover plants, pre-emergent herbicides will prevent clover seeds from germinating. Many pre-emergent weed killers are synthetic, but corn meal gluten is an organic option.
How to prepare corn gluten? ›
Corn which was soaked in 0.3% sulfurous acid solution for 50 hours was crushed in a crusher to separate embryos and octaves, and then the corn was crushed again by grinding to dissolve in water to separate starch suspension and gluten containing 80-90% of water.
Can you use corn gluten meal in a vegetable garden? ›
In the vegetable garden, it can be applied after direct-seeded crops or transplants have become established. As a bonus, CGM contains about 10% nitrogen by volume and can therefore act as a slow-release natural fertilizer for your nitrogen-loving veggies.
What do farmers use to kill weeds in corn fields? ›
Herbicides reduce the early competition of weed infestation, reduce the seed bank, and reduce the potential for competition in the following crop. Preplant, preemergent, or postemergent herbicides are available that will selectively control most species of weeds in corn.
