Crabgrass is a warm season annual grass which grows best in the heat of midsummer when desirable lawn grasses are often semi-dormant and offer little or no competition. Crabgrass overwinters as seed, comes up about mid-May or later, and is killed by the first hard frost in fall.
Crabgrass grows best in full sun. It does not grow in shady places. Crabgrass can be controlled in a number of ways, but the best defense against crabgrass is a thick vigorously growing lawn that is mowed no closer than 2 1/2" for cool season grasses.
Fertilize the lawn in late summer or fall and again in spring to develop a dense, healthy stand of grass. Fertilized bluegrass does not go into midsummer dormancy as soon as unfertilized bluegrass.
Pre-emergent applications made when soil temperature are still below 60 are the best prevention. Pre-emergent applications are not recommended for areas where new grass seed is going to be planted during the first half of the growing season. Pre-emergent applications lose their effectiveness if the lawn is raked or disturbed during the first half of the growing season.
The timing of treating crabgrass is critical and if this is not handled correctly and a post-emergent has to be applied, it will be more costly. When you see yellow flowering Forsythias begin to bloom, this is the time to call us to schedule an appointment for treatment.