Crabgrass germinates once the ground temperature maintains at least 60 degrees Fahrenheit for a full week. Lay seed in early spring once the ground temperature has come up to necessary levels.
Crabgrass reproduces rapidly, releasing up to 150,000 seeds from each plant. Reproduction continues through late summer. Seeds die when the first frost occurs.
Crabgrass is a yellowish-green grass that appears very stiff. Branch-like sprouts appear off the plants as they grow.