How To Get Rid of Nutsedge—an Invasive Weed That Can Take Over Your Lawn

A well-maintained, uniform lawn is something many homeowners desire, but the sight of nutsedge (Cyperus rotundus) can get in the way of this dream. Some may not like the way it looks, and even worse, it's extremely invasive and difficult to eradicate once it establishes itself in your lawn. The good news is that there are ways to get rid of nutsedge naturally. Ahead, our lawn care experts share their favorite pesticide-free methods for eradicating this grass-like weed once and for all.

What Is Nutsedge? 

Nutsedge (also called nutgrass or watergrass) is a weed that resembles grass but is in a different botanical family. It grows in clumps and produces spiky seed heads. "Nutsedge is an aggressive weed that is neither a broadleaf nor a grass-type weed," says landscape designer Teresa Watkins. "It is a sedge that has solid three-sided stems. A popular phrase is 'sedges have edges' when you feel their stems." She explains that certain sedges compete for water and nutrients and can take over an entire landscape. "It spreads by underground tubers that multiply rapidly. If not caught early, nutsedge is difficult, if not impossible, to control," she adds.

How to Get Rid of Nutsedge Naturally

According to Watkins, nutsedge thrives in wet soils, over-irrigated lawns, and soils with poor drainage. If it is thriving in your lawn under these conditions, try these expert-recommended ways to remove nutsedge without using pesticides. Make sure you act fast, as Watkins says removing nutsedge when it is small in early summer is critical.

Try Cardboard

Restricting a plant's access to sunlight long enough can exhaust its energy source and lead to death. "One method is to smother the roots with a material like cardboard or a stack of newspaper," says Gates. She recommends anchoring the material down in windy locations and covering a wider area than you may think. "The roots extend beyond what you can see or readily pull, so while the top of the plant may die from lack of sunlight, the roots contain a storehouse of carbohydrates that readily jumpstart what root piece remains." 

Use Plastic Sheeting

Black or clear plastic, which is available at home supply stores, can also smother nutsedge, says Gates. "The advantage of plastic is the intense heat that can build up. While nutsedge likes warm, moist soil, it can only tolerate so much heat," he says. "Black plastic eliminates sunlight, necessary for photosynthesis, which keeps the plant alive, and it is non-porous, so there is also a lack of oxygen." Once the nutsedge is dead, you can fold the plastic and store it to reuse. 

Remove It Manually

Hand-pulling weeds can be very effective, but it's important to get the entire root. "Nutsedge has incredibly delicate roots that snap off with virtually no pressure. So, even pulling the plant up from very moist soil only eliminates the top of the plant," says Gates. Removing the above-ground portion of the plant minimizes its potential to spread its seeds, but nutsedge also reproduces from its rhizomes underground. For hand-pulling to be successful, you need to dig it up from underground to ensure the removal of the tubers and rhizomes.

How to Prevent Nutsedge From Coming Back

Nutsedge is a vigorous plant, so it will try to come back, even after trying the above methods. According to our experts, prevention is key to ensuring it never returns.

Maintain Lawn Vigor

Nutsedge will have less of an opportunity to invade if your lawn is strong. "Keep your turf healthy and thick," says Watkins. She adds that aerating your lawn regularly can help water and nutrients get down to the roots of your grass, keeping your lawn lush and leaving less room for nutsedge to grow.

Mow for Success

Mowing your lawn at the right height is essential for its success, says Watkins. "Scalping turf grass makes sedge easier to grow," she says. Mowing too short weakens and stresses the grass, creating an open invitation for weeds. 

Mulch Landscape Beds

Areas of your landscape that don't have grass, like your garden beds, can benefit from a layer of mulch to help prevent nutsedge from taking root. "Mulching landscape beds at 3 to 4 inches will help," says Watkins. 

Stop the Life Cycle

Do not let the nutsedge go to seed, says Watkins. While it's difficult to prevent spreading, you can interrupt the plant's life cycle by mowing it before it can spread.

Be Careful When Adding New Plants

When you add new plants to your garden, you run the risk of bringing nutsedge rhizomes home with you from the nursery. Be careful and examine the soil around the rootball if you're unsure.