In the mid-1980s, scientists at Iowa State University discovered that corn gluten meal (CGM) displayed amazing properties in stifling a variety of weeds while nourishing turf grass. Resembling a crunchy breakfast cereal, CGM controls weeds by preventing roots from forming at the time seeds germinate. It poses no danger to children, pets, or wildlife.
On lawns, CGM prevents germination of nearly 90 percent of certain weeds, including crabgrass and dandelions. As it breaks down, CGM releases 10 percent nitrogen. The product must be applied in early spring. A second application between mid-August and first frost controls fall weeds. In beds, CGM can be applied before setting out transplants of summer annual flowers and vegetables.
Gardens Alive ( www.gardensalive.com or 513/354-1482) sells two corn gluten-based products: Original WOW and WOW Plus in 5-, 25-, or 50-pound bags ($9 to $50 each).