Finding Agricultural Corn Meal for Fungal Control

Lynn in Upper Marlboro, MD can't find agricultural corn meal—stores confuse it with corn gluten meal. They're different: corn meal is whole ground corn (fungicidal); corn gluten meal is protein fraction (pre-emergent herbicide).

Sources: nurseries with organic lines (American Plant Food Co. in Bethesda), feed stores (Southern States Cooperative in Upper Marlboro), farm supply (Lesco Service Center). Call ahead. Walmart garden centers increasingly carry organic products.

For immediate fungal issues (powdery mildew, black spot, brown patch): baking soda spray works. 2–3 tbsp per 2 gallons water, spray weekly. For whole-yard treatment, agricultural corn meal applied dry and watered in suppresses soil-borne fungi long-term.

Don't substitute gluten meal for fungicide—it won't work the same way.