Life Cycle and Identification

Yellow nutsedge seems to have survived the heat of the summer and is thriving with the recent heavy rains in our region. This inconvenient perennial weed becomes more problematic during spring and summers with above average rainfall. Remember all the torrential rains and flooding this spring and summer?

Yellow nutsedge actively grows during the heat of the summer when cool-season turf grasses grow more slowly. Yellow nutsedge typically emerges in May or June, a few weeks after crabgrass germinates, and grows actively until first frost. A frost will kill above ground portions but the tubers will survive and overwinter in the soil. Dormant tubers can germinate and emerge throughout the following season.

The seedling looks very much like the desired turf that we want to find and blends in very well when it’s young. Given time, it becomes more noticeable with a light green color and flat, slender cotyledons (seed leaves).

Photo credit: Aaron Patton, Purdue Extension

Photo credit: Corey Gerber, Purdue Extension

Yellow nutsedge can produce seed but also reproduces through tubers and bulbs. Several hundred tubers, or nutlets, can be produced from a single plant during the summer! These nutlets can survive in the soil for several years if conditions are not appropriate for them to grow and produce a new plant. The mature stem is triangular in shape which helps to distinguish it from any other members of the grass family. Lower leaves are arranged in groups of three.

Remember: “Sedges have edges” to help you identify it from grasses.

Site History and Cultural Control Methods

Control of this weed earlier in the season before tubers are formed is the best line of defense. Yellow nutsedge tubers can easily spread by soil, topsoil, or fill dirt from one area to another during construction. Additionally, people and equipment can spread yellow nutsedge any time they move soil while planting or dividing ornamental plants in the landscape.

Yellow nutsedge is most problematic in turf that is mown too short, and it thrives in areas where soils remain moist from poor drainage or overwatering, However, yellow nutsedge can also be a problem in well-drained areas, especially thin turf.

If only a few yellow nutsedge plants are present, hand pulling will help eliminate the weeds but will not remove the tubers in the soil. Several weeks after pulling yellow sedge, check the area to see if the plants have regrown from the tubers. For yellow sedge in landscape beds, it is best to remove the entire plant (including the root/rhizome system) by digging around the plant’s base. This will help ensure that you will not get regrowth from the nutsedge’s underground rhizomes.

Photo credit: Chuck Shuster, Maryland Extension

Photo credit: Aaron Patton, Purdue Extension

Control with Herbicides

Herbicides may be required when large patches of nutsedge are present in the turf. The traditional herbicides used to control dandelions and crabgrass are ineffective since yellow nutsedge is a sedge and not a broadleaf or grass. Herbicides that contain halosulfuron or sulfentrazone are recommended for yellow nutsedge control. Of the two ingredients, sulfentrazone will provide the quickest control. Injury symptoms appear on yellow nutsedge within a few days after a sulfentrazone application. Injury symptoms appear on yellow sedge about two weeks after a halosulfuron application.

Regardless of herbicide selection, yellow nutsedge is a difficult-to-control weed that may require multiple herbicide applications. Follow label directions about when to make follow-up applications, if needed.

Late spring/early summer (when it is young and actively growing) is the ideal time to control yellow nutsedge. During its early stages, yellow nutsedge has not started producing tubers and is most susceptible to control with herbicides. As the summer progresses, nutsedge plants form seedheads and tubers. Since the tubers are the plants’ primary survival structure, it is critical to control nutsedge early in the summer before it produces tubers.

Be patient. Two to three years of control using herbicides will be needed to reduce viable tubers by about 90%. Herbicide applications will injure growing yellow nutsedge plants and help prevent more tubers from forming, but herbicide applications will not control tubers that are viable in the soil but have not yet produced plants.

Before using any herbicide, always refer to the label for specific instructions about proper use and turfgrass tolerance.

Consider the following steps for successful yellow nutsedge control:

  1.  Read and follow all directions on the herbicide label.
  2.  Do not mow one or two days prior to or following the herbicide application.
  3. Treat the area with the proper rate of herbicide and volume of water listed on the product label. Do not apply the herbicide if the turf is stressed due to drought or high temperatures.(≥90°F).
  4. Six to ten weeks after the first application, repeat steps 2 and 3 if the yellow nutsedge has recovered or regrown from tubers.


In summary, sedges are problem weeds and are difficult to control with nonchemical options. Many herbicides are available for sedge control but proper herbicide use and application timing is critical to optimize control.

For best results, apply herbicides prior to tuber production. The most common mistake is to apply herbicides too late in the season after yellow nutsedge is big, spreading by rhizomes, and producing tubers. To be effective, you will need to implement a sedge control program early in the season and continue it for more than a year to reduce tuber populations in the soil and prevent the spread of this problematic weed.