If it has been six to eight weeks since your early spring fertilizer application, then it’s the perfect time. Green-Up Weed & Feed is both a lawn food and a broadleaf weed herbicide. In fact, unlike the National Brand, which kills approximately 70 weeds, Green-Up Weed & Feed kills over 250, including dandelions, clover, chickweed, and oxalis! Apply Green-Up Weed & Feed when the air temperature is below 85° and the humidity is low. Additionally, remember to apply it to a damp lawn so that the herbicide sticks to the weed leaves. Please make certain that no rain or irrigation happens for 48 hours after treatment. Raining or watering before this time will wash the herbicide off the leaves and render weed control ineffective. For similar reasons, stay off the lawn for the same time period. You may water – and resume normal traffic - after the 48-hour time period is over.