Most people don’t notice crabgrass taking over their lawns until summer. This voracious, fast-spreading weed is at its most productive during the warm summer months. As crabgrass spreads, it steals nutrients from the grass. By the time you notice it, chances are the crabgrass is established. Here’s how to prevent crabgrass, or eradicate crabgrass once it’s in your lawn.
How Crabgrass Spreads
Each crabgrass plant has thousands of seeds in the fall, then dies. The seeds lie dormant over the winter and germinate in the spring. With all those seeds sprouting at once, you are likely to have a major infestation.
Your best bet to prevent crabgrass is to stop the seeds from sprouting. This will break the growth cycle. The best defense is a healthy lawn. A thick, lush lawn makes it difficult for crabgrass to take establish itself after germination. Good lawn care like regular (deep) watering, cutting no more than one-third of the grass leaf at a time, and regular aeration/dethatching are important to preventing crabgrass. And if your lawn is healthy, the crabgrass will be noticeable as soon as it starts to spread, allowing you to control it.
Keep an eye out for crabgrass in the spring; the sooner you notice it, the easier it will be to control and eradicate it. These are your best options:
- Pre-Emergent Herbicide: These are designed to kill crabgrass seedlings in their early stages of growth. Ideally, apply as soon as the ground temperature reaches 60 degrees—which, for most regions, is fairly early in the spring (as soon as your local trees start budding). Because this herbicide can be rough on new grass, don’t use it on recently seeded lawns.
- Regular Herbicides: Crabgrass is resistant to regular weed killers, including weed and feed fertilizers and anything designed to kill broadleaf weeds. Stronger herbicides may kill your lawn along with the crabgrass. Spot-killing crabgrass by spraying is your best bet.
- Crabgrass Killers: Specialty herbicides for crabgrass should use according to the exact directions on the label. In almost all cases, spray when temperatures are below 85 degrees, and avoid mowing, watering, and walking on your property for a few days afterward. Early summer and early mornings are the best time to treat.
- Non-Chemical Options: You can pour boiling water directly on the crabgrass plants, or pull them by hand (make sure you get the entire root). This is time and labor-intensive. Reseed any areas immediately afterward.
Crabgrass prevention is the best option, so come up with a plan of action to keep your lawn lush, green and healthy. By staying on top of lawn care tasks like seeding and aerating, it is possible to stop crabgrass from getting a foothold.