Jonathan Green Green-Up Crabgrass Preventer Lawn Fertilizer For All Grasses 15000 sq ftJonathan Greens Crabgrass Preventer plus Green Up Lawn Fertilizer feeds the lawn for up to three full months and provides pre emergent control of crabgrass. When applied prior to germination it controls other weeds such as goose grass, dallies grass, chickweed, henbit and oxalis. This product contains an advanced herbicide known as Dimension that provides postemergence control, meaning it will kill existing weeds, such as crabgrass, even after they