Crabgrass (or crab grass) is an aggressive, invasive, grassy weed named for the way it sprawls--crab-like--from a central root across the ground. It can easily get out of control in your lawn if you don't take measures to stop it.
Best Growing Conditions
Before you learn how to control crabgrass, it's helpful to understand how it thrives and multiplies in your lawn.
Crabgrass loves the hot, dry conditions of summer. It is an annual that dies off in the winter - but not before it distributes thousands of seeds in mid-summer that lie dormant until they're ready to sprout in the spring (when temperatures reach about 60 degrees F).
It is difficult, if not impossible, to prevent seeds from blowing around your neighborhood onto to your grass. But it is possible to create an unfavorable environment for crabgrass to grow.
Kill Crabgrass Seeds Before They Germinate
While you can't keep every crabgrass seed from landing on your lawn, it is possible to keep the seeds from germinating:
- Raise your mower blades and keep the grass long (shade discourages growth).
- Eliminate any bare spots (which crabgrass easily populates).
- Keep your lawn well watered and fertilized, particularly in early spring when crabgrass first emerges.
If Crabgrass Emerges
If you do see crabgrass in your lawn, get rid of it before mid-summer when it goes to seed:
- Hand pull any crabgrass you see (usually an easy task because of the weed's shallow root system).
- Use vinegar or boiling water to kill large patches of crabgrass (but remember this kills any grass it touches, as well).
- Reseed or sod the area immediately to prevent crabgrass from taking root again.
- Use herbicides as a last resort.
