How to Treat Nutsedge Weeds

Pull out the nutsedge weeds from your yard if the infestation is small and only a few plants exist. Using a hoe or shovel, dig 8 to 12 inches deep and 10 to 12 inches beyond the perimeter of the invasive plants to ensure you collect all the rhizomes and leafy growth. The ideal time to dig the plants is in early spring, before they produce rhizomes.

Treat your yard with dichlobenil, a pre-emergent herbicide, in parts where you previously encountered a nutdege problem or suspect the weeds to be growing. The active ingredients in the herbicide prevent the plants from seeding, curbing growth and spread. Read label directions for application rates.

Spray a post-emergent herbicide like glyphosate over actively growing nutsedge weeds in the yard. The herbicide damages plant tissues, causing death within four to seven days. Cultivate or rake dead nutsedge weeds from the yard, along with their roots, and discard in a knotted garbage bag. You may need to repeat the herbicide application for stubborn or large weeds.

Treat tiny nutsedge weeds with a post-emergent herbicide like MSMA or halosulfuron, preferably before the development of its fifth-leaf stage. Because young weeds draw energy from their leaves, the herbicide on the foliage easily translocates to the tubers, causing death. Repeat application over stubborn weeds after three to four weeks.

Spread agricultural fabric over nutsedge weeds that prevents access to direct sunlight and smothers them. Weigh the edges of the sheet with bricks or rocks to keep it in place during winds. The weeds die in six to eight weeks.