Pre emergent herbicide for crabgrass

Asked March 18, 2015, 3:25 PM EDT

I live in Smyrna DE. When is the best time to apply a pre emergent herbicide for crabgrass prevention? Thanks

Kent County Delaware

1 Response

Crab grass generally germinates when the soil temp is between 50 and 57F just below the surface for 3 days. The pre ememgent should be down before that occurs. This generally corresponds to the blooming of forsithia. The Delaware Liveable Lawn program recommends putting down the herbicide in April. Before you apply the herbicide make sure the lawn is free of weeds and debris that would prevent the pellets from reaching the soil suface. Water after applying. If there are any areas that you expect to reseed do not put down the herbicide in these areas. Do not aerate or dethatch after applying. Good luck wth the lawn. Tony