Corn Gluten - Ask Extension
When should I apply corn gluten to my lawn this year to help prevent weeds? I know it's before they germinate but I don't know when to expect that. I ...
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Corn Gluten #823179
Asked March 22, 2023, 11:10 PM EDT
When should I apply corn gluten to my lawn this year to help prevent weeds? I know it's before they germinate but I don't know when to expect that. I have mostly dandelions, chickweed, vineweed, and crabgrass. Thank you, Margie
Arapahoe County Colorado
Expert Response
Thank you for your timely question.
Corn gluten should be spread on your lawn in late March to mid-April. Corn gluten works by inhibiting root development in emerging weeds. It must be applied before weed germination which is why it is classified as 'pre-emergent'. It is good to note that it is not selective in only targeting weeds, any emerging seedling can be affected by corn gluten. It is an organic pesticide and does have about 10% nitrogen content. Lawns need nitrogen for good growth and lawn thickness. A healthy lawn will "out compete" weeds.
CSU Fact Sheet, 3.101: https://extension.colostate.edu/topic-areas/yard-garden/control-of-annual-grassy-weeds-in-lawns-3-101/ mentions corn gluten meal as a good control for crabgrass and foxtail weeds. Also there are tips for non-herbicidal weed control in the Fact Sheet.
A number of universities have performed trials on the effectiveness of corn gluten with mixed results. Some trials found it to be effective and some trials found no benefits. Research is on-going.
It would appear that the biggest downfall to the use of corn gluten meal as a pre-emergent is the cost. The recommended rate of use is 20 lbs. per 1000 square feet. That can carry a pretty hefty price tag.
I hope you have found this information useful.
Corn gluten should be spread on your lawn in late March to mid-April. Corn gluten works by inhibiting root development in emerging weeds. It must be applied before weed germination which is why it is classified as 'pre-emergent'. It is good to note that it is not selective in only targeting weeds, any emerging seedling can be affected by corn gluten. It is an organic pesticide and does have about 10% nitrogen content. Lawns need nitrogen for good growth and lawn thickness. A healthy lawn will "out compete" weeds.
CSU Fact Sheet, 3.101: https://extension.colostate.edu/topic-areas/yard-garden/control-of-annual-grassy-weeds-in-lawns-3-101/ mentions corn gluten meal as a good control for crabgrass and foxtail weeds. Also there are tips for non-herbicidal weed control in the Fact Sheet.
A number of universities have performed trials on the effectiveness of corn gluten with mixed results. Some trials found it to be effective and some trials found no benefits. Research is on-going.
It would appear that the biggest downfall to the use of corn gluten meal as a pre-emergent is the cost. The recommended rate of use is 20 lbs. per 1000 square feet. That can carry a pretty hefty price tag.
I hope you have found this information useful.
