17-0-0 fertilizer w/.15% Dimension 50lb bag covers 10-12k square feet. It can be applied as Step #3 in our fertilizer program, best time to apply for control of crabgrass is 1st or 2nd week of May around here. Can also be applied as Step #1. Dimension specialty herbicide provides preemergence and early postemergence control of crabgrass, along with preemergence control of more than 45 other grassy and broadleaf weed species. It offers proven control wherever it’s applied Time-tested quality Proven Trusted Nonstaining formulation Wide application window