crabgrass pre-emergent

Asked June 15, 2015, 7:51 AM EDT

Good morning, Is it too late to put down a second application of crabgrass pre-emergent? First one was done in late March; for the past 2 years we have done a second application, based on UMd recommendations. Very little crabgrass found in turf. Thanks.

Anne Arundel County Maryland

1 Response

Crabgrass will germinate throughout the summer months. Pre-emergent herbicides will be effective for approximately 90 days, depending on the amount and active ingredient applied. Our recommendations are to apply a second application 6 weeks after the initial application.Frequent rains will diminish the effectiveness of the herbicide during wet summers.If crabgrass has been a problem in the past, it is suggested to apply the second application now.