Scotts Turf Builder Halts Crabgrass Preventer with Lawn Food pre-emergent weed killer plus fertilizer stops crabgrass before it invades and protects all season long. It also prevents other listed grassy and broadleaf weeds, including barnyard grass, foxtail, Poa annua, chickweed, and oxalis. The added fertilizer feeds for a fast green-up after winter and helps build strong, deep grass roots. Apply in early spring (prior to 3rd or 4th mowing) when your lawn is dry and before temperatures are regularly in the 80s. Manufacturer recommends using a spreader to apply this product. For Scotts broadcast/rotary spreaders, use a setting of 3. For Scotts drop spreaders, use a setting of 6. For best results, the lawn should receive 1/4 In. of water from rainfall or watering within 2 to 3 days after application. Rain, snow, or freezing conditions after application will not affect the performance of this lawn care product. Do not apply to Dichondra and Bentgrass.