Corn gluten meal for weed control?

Q. In your recent article you mentioned using the above product to eliminate weeds and seeds of all types. We have a round pen used in training horses and every year we have weeds growing when the pen is not used. We want to eliminate the weeds without using roundup to do it. If the corn gluten meal works I would like to know where it can be purchased and if it has to be one on a regular basis. Thank you in advance for you help…
Doug Drenik, Warsaw (Owen Electric Cooperative)

A. Hi, Doug: Corn gluten meal would be a great option to keep your round pen free of many broadleaf and grass weeds while it is not in use. It will not do anything if you have existing weeds but I imagine the horses are taking care of that. Corn gluten meal (CGM) is an organic pre-emergent herbicide that eliminates future weeds by inhibiting root development.

Timing is crucial in terms of application and you will want to water the corn gluten meal after application but then it needs to remain dry for a few days to be effective. Corn gluten meal is available in pelletized, granulated and unprocessed form. Each product, depending on form, will indicate application rates. Typically it is applied in the early spring and then again in the fall.

Check with your local garden or feed store centers to see if they carry this product. if not, they may be able to order it for you or it can be purchased online. I hope this is helpful.