Weed controlling an organic lawn with corn gluten
The mechanics of weed control centers on growth regulating and inhibition of root formation at the time of germination. The ideal way to achieve control is to apply this material a few weeks before germination. Water it in if there is no rain. A short drying period is needed for death of weed seedlings during the critical time when no root system has formed. If the soil surface remains wet during the germination period, affected plants may recover and resume rooting. Corn Gluten Meal has the potential as a natural pre-emergence herbicide. There is no post-emergence effect of Corn Gluten Meal on weeds, the effect is entirely pre-emergence.
What is Corn Gluten Meal
Corn Gluten Meal is a 60% corn protein material that is approximately 10% nitrogen (by weight) which makes it an excellent organic fertilizer. It is a byproduct of the wet milling process. It is sold as a feed for cattle, poultry, and is a primary constituent of some dog food products.
Corn Gluten Meal reduced plant survival and root development by 75% on black nightshade, common lambsqarters, creeping bentgrass, curly dock, purslane, and redroot pigweed. Corn Gluten Meal reduced plant survival and root development by 80% on catchweed bedstraw, dandelion, giant foxtail, and smooth crabgrass. Barnyard grass, quackgrass, and velvetleaf were the least susceptible species showing survival reductions of 30%.