Crabgrass is taking over my yard, what can I do to get rid of it?

Published 8:03 pm Thursday, August 23, 2018

This has been a recurring question for the last few weeks. Nothing causes an immaculate yard to look worse than an infestation of crabgrass. Crabgrass is a summer annual that germinates when springtime soil temperatures reach 55 degrees. The past few years, eastern North Carolina soils reached the optimum temperature between the second and third week of February. Once crabgrass has germinated, studies have shown that freezing temperatures will not necessarily kill it. Crabgrass will continue to germinate through mid-May.

How do you control crabgrass? Have you heard of the 12-step plan? Here is a DIY 4-step plan to control crabgrass. The first step is knowing what type of warm-season grass you have. If you need help with identifying your turf, a visit to or your local extension office is in order. Turffiles is an award-winning turf management website with content from N.C. State University. It is important to know what type of turf you have, because not all herbicides will work on all grasses. The second step to controlling crabgrass is to select a pre-emergent herbicide that works with your grass and has a good rating for preventing germination of crabgrass. The third step is application timing. If the weed has germinated, a pre-emergent herbicide will do nothing to control it. An application between mid-January and early February will ensure adequate early season control. A fourth step that may be necessary is a follow-up post-emergent herbicide that is suitable for your turf and labelled for crabgrass applied after green-up of the turf. Full green-up is typically in early to mid-May depending on the season.

When selecting an herbicide, do your homework or contact your extension agent for help with choosing. Always remember to follow the label, the label is the law. Be very cautious with using weed and feed products on warm season turf. Weed and feed is a combination of fertilizer and herbicides designed to kill weeds while fertilizing the grass for the season. The timing of the application is not necessarily good for warm season turf, the fertilizer application is early for warm season turf and the pre-emergent herbicide is late to control many of the summer annuals. In addition, most weed and feed products are very harmful to centipedegrass. Separate applications of herbicide and fertilizer give a much better bang for your buck and are better for your turf. Fertilize most warm-season grasses after green-up and according to your turf type thereafter.

Once crabgrass is allowed to mature, it can be very difficult to control. There are very few selective herbicides that work well to kill crabgrass at this point. The best remedy for weeds in turf is to maintain a happy healthy stand of turfgrass. This requires proper management of cultural practices and soil sampling. Mow your grass at the proper height for the cultivar. Fertilize and lime according to soil reports and recommendations to maintain fertility and pH at optimum levels. Turfgrass management calendars can be found at for each species of warm-season grass. These calendars offer a management schedule, based on the season, to maintain the best stand of turf possible.

If you have a question to submit, please email to Gene Fox at Having trouble with growing in your home landscape, call the Extension office and speak to an Extension master gardener volunteer Mondays and Wednesdays between 10 a.m. and noon at 252-946-0111. The master gardener volunteers will also be at the Washington Farmers’ Market on Saturdays throughout September to answer questions and diagnose problems. Be on the lookout for the October “What You Need to Know So You Can Grow Series!” Learn more on Facebook at the Blacklands Area Horticulture page or visit the Extension Office located at 155 Airport Road.