Usually early March in the Mid Atlantic region is the best time to apply Crabgrass preventer. It is most effective when soil temperatures range from 50 degrees to 65 degrees Fahrenheit. Crabgrass preventers are used to prevent crabgrass seed from germinating, therefore reducing the amount of the dreaded weed in your lawn. For long term success, the preventer should be applied each spring. A healthy lawn adds competition for crabgrass and helps lower the infestation.
Meadows Farms recommends Pennington’s Ultragreen Crabgrass Preventer plus Fertilizer. Spring is the best time to use weed controls in the lawn. By reducing the weeds your lawn has time to establish itself before the long hot summer.