In Spring when should pre-emergent weed killer be applied?
If you had a crabgrass problem last season it is recommended to apply a crabgrass premergent this spring. Crabgrass seeds germinate when the soil temps average 55 degrees for 7-10 days. You can apply when the forsythia shrubs are in full bloom in your area. Look for a product that does not contain fertilizer and follow all label directions. For more information see the attached publication on crabgrass http://www.mdturfcouncil.org/admin/uploadfiles/tt-43e-crab.doc