Corn gluten is a great alternative to chemical herbicides in controlling weeds. It is safe for pets, children, and wildlife. However, most gardeners are not aware of when and how to apply the corn gluten meal on their lawns for effective weed control.
Apply corn gluten in late winter to early spring when most weeds are germinating. Spread the liquid, powder, or granular treatment evenly over the lawn and water slightly. Be sure to read the manufacturer’s directions on the product label.
Corn Gluten Meal for Lawns – How it Works
Just like pre-emergent herbicides, corn gluten meal can effectively control the emergence of lawn weeds including crabgrass, dandelion, nutgrass, pigweed, and other dicot weeds. It is a non-toxic organic herbicide that won’t damage your lawn. It is also known to have nutritional benefits for lawn grasses and other plants.
Corn gluten is a byproduct of corn milling that has historically been used as a supplement in animal feed. This product was discovered to kill weeds before they establish. Corn gluten does not prevent weed seeds from germinating but inhibits the young weed plants from developing roots.
The newly germinated weed plants are thus left without a mechanism to absorb water and they quickly die of dehydration. The application of this organic weed killer has to be timed just when the weeds have germinated.
Corn gluten meal becomes ineffective when applied any time before weed seed germinates or after the weed plants have established and grown strong root systems. At this time, the product will only serve as a fertilizer for your grass and the weeds as well.
When to apply corn gluten on your lawn
The majority of weed seeds germinate during late winter and early spring. This is the period when forsythia plants bloom before even their leaves emerge. Apply the corn gluten meal during this short window in which the dreaded crabgrass and other weeds are germinating.
To effectively prevent winter annual weeds such as bittercress, deadnettle, henbit, chickweed, or other perennial weeds whose seeds usually germinate in the fall, apply the corn gluten meal in the late summer, as soon as daytime temperatures start to decrease.
Further, the amount you apply will also determine how fully it will defeat the weeds. The recommended rate of application is 20 lbs. of corn gluten per 1,000 square feet of lawn. Anything short of that means money has gone down the drain.
The effectiveness of corn gluten also depends on your watering or rainfall pattern. After the application, the product needs to be driven into the soil by watering or rainfall. Ideally, a watering or rainfall of about 1/4 inch is great for the application of corn gluten.
That is not all, a short dry period of three to seven days is necessary to completely deny the germinated weeds some water. While it can be difficult to achieve this with rainfall, it is much more possible with artificial watering.
Another application after one month or in late summer will guarantee full control of the weeds.
In addition to natural pre-emergent weed control abilities, corn gluten also serve as plant food. It contains about 10% nitrogen by weight in an organic form which is released slowly into the soil as it decomposes over a period of 3-4 months.
How to Apply Corn Gluten Meal on your Lawn
Corn gluten meal is available in most garden centers in liquid, granular, or powder form. To apply corn gluten meal as a weed treatment, spread it evenly over the lawn as directed on the label by the manufacturer and water slightly.
Do NOT use the corn gluten meal when seeding a new lawn or over-seeding. It may prevent the seed from germinating.
The downside of using corn gluten
While your lawn or garden plants may reap big from corn gluten meal, there are a few disadvantages to expect.
- Existing weeds may also benefit from the fertilizer when applied at the wrong time, which may bring even a bigger weed problem to your lawn.
- Corn gluten is more expensive than chemical pre-emergent herbicides. The cost of corn gluten meal has been rising yearly.
- Seed germination sometimes varies based on the species of the weed and changes in climatic conditions. It may not be easy to time appropriately. This is why most gardeners end up frustrated after spending thousands of dollars without achieving good results.
Final Thought
Corn gluten meal is a great alternative to conventional pre-emergent herbicides, however, timing is very critical in achieving full weed control. When applied consecutively for several years, corn gluten meal will effectively suppress weeds for good.
Additionally, healthy lawn care practices such as proper watering, weeding, and mowing will give your grasses an advantage over undesired weed plants.
References
- Iowa State University Extension: Corn Gluten Meal – A Natural Weed and Feed for Lawns and Gardens
- University of Maryland Extension: Corn Gluten for Crabgrass Control