A common enemy

Post-emergent applications can help get rid of stubborn weeds that keep coming back.


Battling crabgrass is a constant struggle throughout the U.S., no matter what type of grass you’re dealing with. “It’s the weed we get the most complaints about,” says Jim Stockhardt, operations manager at Evergreen Lawn Care in Cherry Hill, New Jersey.

While a pre-emergent herbicide can stop crabgrass in its tracks, post-emergent products are a viable option as well. Warm weather and wet conditions in many parts of the country are facilitating crabgrass germination, and the rains reduce the efficacy of pre-emergent applications.

Crabgrass is particularly tricky because while freezing weather destroys a lot of weeds, crabgrass seeds will pop up again the following year without fail. While pre-emergents are the first choice for these hardy plants, heavy rains can thwart efforts. Or, your new customers may call you once they start noticing problems on their lawns. In those cases, post-emergents can save your customers’ lawns.

To find it fast, look in thinner or shorter grass areas since they warm up first, making it easier for crabgrass to take over, Stockhardt says. Look for plants with wider or lighter leaves than the turfgrass, and look for matted areas. “If it’s far enough along, you’ll see big mats among the grass,” he says. “You can’t really miss it.”

The earlier you can treat it, the easier it will be to control because as crabgrass matures, more applications will be necessary. In fact, one or two applications probably won’t be enough, no matter how quickly you get them down, Stockhardt says. “We usually have to put down at least three applications if something gets through the pre-emergent,” he says. “It’s a tough weed to get rid of and you find it all the time on lawns where the grass isn’t well-established or healthy enough.”

Stockhardt says he’s had to remove enough patches of crabgrass in customers’ lawns, which isn’t ideal, and not just for aesthetic reasons. “Bald spots are ripe for other weeds to come in and take over,” he says, noting that this is usually a problem for new customers since his company always sprays pre-emergent herbicide in the spring. “You really don’t want to give them the opportunity to get in there because that will just lead to more call-backs and more unhappy customers.”

The best offense is a good defense, and not just for crabgrass control. A higher mowing height, good fertilization practices and regular soil tests are all key for discouraging crabgrass, Stockhardt says. Although, no matter how many times he tries to tell his customers to keep grass at about 3 inches high, there are always some who insist on mowing every week.

“It’s just ingrained in them somehow,” he says. “There’s just no talking to some people, but crabgrass loves short grass, so they’re going to keep running into problems. Luckily, we’re only a phone call away.”