Ever notice those little signs that are posted on lawns after herbicides are
used and think, "There has to be a way to do this without using something poisonous?"
There is - and it's not only good for your lawn, it's non-toxic. It even helps the
environment by taking a by-product of the milling process for corn (yes, corn!) that mills
formerly dumped into landfills as 'useless.'
What is it? Corn gluten. Nick Christians, Ph.D., a researcher at Iowa State
University discovered that corn gluten meal (also known as sixty-percent protein corn gluten
to the livestock industry) inhibits the germination of all sorts of weed seeds that we don't
like in our lawn.
Which weeds? Dandelions, crabgrass, creeping bentgrass, foxtail, lamb's-quarters,
purslane and redroot pigweed just to name at few. At the same time, it is a ten-percent nitrogen
fertilizer that lawn grasses absolutely love.
How do you use it? As a pre-emergent herbicide, apply corn gluten meal at 20 pounds
per 1,000 square feet. You use a regular drop spreader (you can get the meal as both a powder, which is
cheaper, or pelleted - a drop spreader will work for both). This will significantly reduce germinating
weeds in the first year, and the more years you use it the better it works (established weeds die
from old age or from digging out, and new weed seeds can't germinate).
It will not kill weeds that are already established, but it will kill any weed seeds
that are ready to germinate. To use it as a pre-emergent you must spread it before the weeds germinate,
which means in early spring (in Wisconsin, for example, a good rule of thumb is put it out before April
15th. Earlier is fine - snow on top of it won't hurt it, nor will cold weather).
As a fertilizer, you can use corn gluten in the fall (or during the summer) just the
same way you would any other lawn fertilizer, again at 20 pounds per 1000 square feet. A bonus: if you
overdo it, it won't burn the grass. Be careful though - you can't plant grass seed for a few months after
you use corn gluten (or many types of annual or perennial seeds) because it will inhibit their germination
too. You can plant grass seed before you put out the gluten, but make sure the seed has time to germinate
and establish itself before fertilizing with the corn gluten.
According to Mike McGrath, former editor of "Organic Gardening," the original
marketer of the stuff is "Gardens Alive!" They're a mail order outfit (phone: 812-537-8651), but
they also have organic garden product sections in many of the Wild Bird Center chain stores around the
country. Their brand name for the gluten/herbicide used to be AMaizing Lawn but now they sell it as
"WOW! Plus" because it also fertilizes while it prevents weed seeds from germinating.
McGrath says it's getting more and more available and is sold under a variety
of brand names, and also mentions that you can try and find plain old bulk corn gluten meal (something
feed mills usually carry, at about $15 per 100 pounds).
How safe is corn-gluten meal? Currently, it is sold as feed for cattle, poultry,
fish, and is the base for many dog foods. It's a by-product of the wet-milling process for corn.
It's just part of the corn kernel, left over when the food-industry mills the corn for other products.
It's as non-toxic as you can get - as safe as the dry food in a dog's dinner dish!
Corn gluten meal. It kills weeds, it fertilizes your lawn, helps our environment
by keeping a useful product out of landfills, and is non-toxic to boot. Why use anything else?
1 McGrath, Mike "Corn meal gluten organic weed preventative"
2 Christians, Nick., PhD. "A Natural Product for the Control of Annual
Weeds." Golf Course Management, October 1993, pp. 74-76.
3 Barbara Bingaman and Nick E. Christians. "Greenhouse Screening of Corn
Gluten Meal as a Natural Control Product for Broadleaf and Grass Weeds. Hortscience 30 (6): 1256-1259.
4 "Gardens Alive!" 5100 Schenley Place, Lawrenceburg IN 47025
The photos that appear within this article are derived from stock photographs obtained
from the USDA ARS archive, and used here for non-commercial purposes.