GreenView Fairway Formula Spring Fertilizer + Crabgrass Preventer is a premium quality lawn fertilizer that toughens, greens and thickens your lawn. Plus, it prevents crabgrass and other grass and broadleaf weeds (see label for a complete list) for up to 4 months when applied prior to germination in lawns. The crabgrass killer for lawns also provides post-emergence control of seedling crabgrass for up to 4 weeks after it germinates. Special extended time-release feeding of nitrogen lasts up to 12 weeks, without surge growth. Apply this formula any time lawn is actively growing. This slow-release fertilizer works on any type of grass; will not burn lawn. Promotes a deep green turf color with fewer grass clippings.