Crabgrass is one of the most prevalent noxious grasses in ornamental landscape areas, and is a severe problem in turf grass areas. This common problem grass is annual and reproduces by seed. Before germination can occur soil temperatures must reach 55 degrees. Crabgrass problems mainly occur in thin and heat stressed areas. This grass is most commonly found along drives and sidewalks, where heat radiates and stresses your normal turf grass. These areas need frequent attention and watering to avoid thinning, which allows the crabgrass to move in.
Pre-emergent herbicides prevent annual grassy weeds such as Crabgrass, Goose Grass, and Foxtail from germinating. Germination starts to occur in April so it is very important to apply your pre-emergent as soon as possible in early spring for proper Crabgrass control.
The best way to prevent problem grasses from invading your lawn is implementing proper lawn care practices. Encouraging dense stands of vigorous grass is will leave no room for Crabgrass to take hold. For example, mowing height can have a major impact. Lawns mowed higher (over 3 inches) tend to have less problems with annual grasses such as Crabgrass. Proper watering is also important to keep the lawn healthy, which will prevent thin areas that Crabgrass will rapidly move into.