By applying crabgrass preventer in the form of granular material to the entire lawn, it will dissolve and form a thin barrier near the surface of the soil which intercepts the germinating crabgrass seeds. When the germinating seed comes into contact with the product, it stops growing.

Do you water in Halts Crabgrass Preventer?

Unlike broadleaf weed killers in weed and feed products, crabgrass preventers do little good sitting above the soil's surface. Watering helps break down the pellets and works the chemicals into the soil.

When should you put down halts?

Apply in early spring to prevent the germination of crabgrass, chickweed, poa annua, and other common lawn weeds, before they start to spread. Apply before the 3rd or 4th mowing to protect all season long.