Answer: Crab grass is an annual weed that grows from seed each spring. It is usually treated by applying a pre-emergent crabgrass preventer product such as corn gluten in early spring, about when the forsythia blooms in your area. It is applied so early because it germinates very early in the season. These products work by preventing the crabgrass seeds from germinating and so can't be used at the same time you seed a new lawn -- they will prevent the desired lawn grass from germinating also. It is always a race to get the lawn grass up and going before the crabgrass takes over, unfortunately.
Q&A Library Searching Tips