You may have missed using a pre-emergent crabgrass preventer (read more on preventing crabgrass here) or put it on too late this spring, but all hope is not lost.
Biology
Crabgrass is a warm-season annual that grows best in the middle of summer when the temperatures are hot. It is not shade tolerant so you will see it congregate along sidewalks or in cracks, on the edge of the lawn by the road or your driveway. The plant winters over as seed and comes up in mid to late-May. The plant itself is killed off by fall frost.
Crabgrass is much easier to prevent than kill, so it is always a good idea to use a pre-emergent in the spring. If the time to apply a pre-emergent has passed there are some ways to help prevent crabgrass from germinating:
- Keep mower height at 2.5 to 3 inches during the warmer months. This will increase shade on the surface and decrease the chance of crabgrass seeds from germinating.
- Keep a healthy lawn and fill in bare spots with grass seed. The less open soil there is, the less likely crabgrass seeds will germinate.
In cases where these steps did not do the job, there is a wonderful product to eradicate the problem. The post-emergent crabgrass and broadleaf weed killer Weed Out will kill crabgrass and dandelions, but won't hurt your lawn. Follow all directions. Use only when daytime temperatures are under 90 degrees.
