28 May How to Use SedgeHammer+ to Control Sedge
How to Use SedgeHammer+ to Control Sedge
Unlike other common lawn weeds, sedge does not fall into the grassy or broadleaf weed category but is instead a class of its own. Although similar in appearance to a grass, it can be differentiated by its shiny yellow-green color and V-shaped stem that will feel triangular in your hand when it is rolled between your fingers. Found throughout the United States, it is quite common to see sedge in moist areas of the lawn that are poorly drained, especially during periods of hot weather. This Sod University article discusses the characteristics of sedge (or nutsedge) and highlights the weed control product SedgeHammer+. First, let’s talk about sedge and its characteristics. Click here to skip ahead to the How to Kill Sedge with SedgeHammer+ section.
Sedge Characteristics and Traits
Sedge can be seen for the majority of the year, but is typically most active and noticeable during the summer when it grows faster and taller than the turfgrass it is invading. Normally, the plant emerges towards the end of April and into the beginning of May and will continue to grow until a frost hits. Since yellow and purple nutsedge are perennial, the above ground tissue will die in the cold while the below ground portion will survive in the soil and germinate the following season. Unfortunately, sedge plants produce underground tubers that can remain even when the plant is pulled out of the soil, resulting in the germination of more plants. In fact, one sedge plant alone can produce hundreds of tubers when it is actively growing.
Pictured above from left to right: yellow nutsedge and purple nutsedge.
Sedge is often recognized by its spiky seed heads represented in the yellow and purple nutsedge images above. In a well maintained lawn, however, sedge becomes hard to recognize with frequent mowing because the weed doesn’t get the opportunity to sprout seed heads. The images below demonstrate the sedge plant before it reaches this point. This is usually how most homeowners will see sedge growing in their lawn if the weed is present.
Pictured above: images of sedge before sprouting seed heads.
Non-Chemical Control of Sedge
To begin controlling sedge, start by identifying cultural problems in your lawn including over watering and thinning turfgrass. The most important step that can be taken in controlling this weed is the maintenance of a lawn that is dense, healthy, irrigated and fertilized on a proper schedule. Some tried and true methods of control include keeping your lawn fertilized with LawnifiTM, which provides the grass with the nutrients it needs to stay dense and healthy so that it can keep sedge away. A strong, dense lawn will outcompete weeds.
Sedge thrives in areas of turfgrass that have moist soil and are mown too short or are thin. Therefore, ensuring that your irrigation system is correct and raising your mowing height will help your lawn to outcompete potential sedge problems. Hand weeding is also an option if the problem is detected early; however, because of its extensive tuber system, it is essential to be thorough when removing the weed. To do so, digging around the base of the sedge may be necessary to loosen the soil and remove its below ground system. It is also important to check the area frequently after weeding in case additional plants develop afterwards.
How to Kill Sedge with SedgeHammer+
Chemical control is also an option if the problem cannot be controlled by cultural practices or hand weeding. One of the most effective post-emergent control options is SedgeHammer+ (active ingredient Halosulfuron-methyl), which can be mixed with water and spread evenly over the grass and weeds. SedgeHammer+ works best when applied in the spring and when the sedge plants have between three to eight leaves or produces tubers. As a selective herbicide, SedgeHammer+ offers control over both yellow and purple nutsedge, kyllinga and other listed broadleaf weeds on the product label below.
SedgeHammer+ is a systemic, post-emergent herbicide meaning that it works best when applied on sedge after it has emerged from the soil’s surface and works systemically through the plant’s system to kill it. The chemicals move through the plant’s system slowly so that it can effectively reach the whole plant and roots as much as possible. Sedgehammer can take somewhere between three to five weeks to kill down to the root and can be reapplied after six weeks if a second application is needed. One final post-emergent, Tenacity herbicide (active ingredient mesotrione), can control some sedge in combination with other broadleaf weeds and may be a good option if multiple weeds are occurring in your lawn. However, Tenacity is only labeled to control yellow nutsedge, not purple nutsedge or kyllinga.
SedgeHammer+ Product Label
How to Use SedgeHammer+
SedgeHammer+ Application Instructions
A single packet of SedgeHammer+ covers 1,000 sq. ft. in your yard. Apply SedgeHammer+ for post-emergence control of purple or yellow nutsedge, kyllinga and broadleaf weeds. Mix 0.5 oz. (13.5 grams) of this product (one pouch) in one gallon of water to treat 1,000 sq. ft. of turfgrass. Mix or shake the solution to ensure ingredients are completely dispersed. Spray the target weeds thoroughly and wet the entire leaf surface of the undesirable plants. For best results, spray nutsedge after it has reached the three to eight leaf stage of growth.
SedgeHammer+ can be safely used on a variety of cool and warm season turfgrasses including the following: creeping bentgrass, fine fescue, perennial ryegrass, Kentucky Bluegrass, tall fescue, bahiagrass, bermudagrass, buffalograss, centipedegrass, seashore paspalum, St. Augustinegrass, kikuyugrass and zoysiagrass.
Before attempting to treat sedge with chemicals, it is important to read the product label carefully to ensure that it will be compatible with your turf and not cause any damage. Refer to the product label above for a full list of application and mixing instructions.
Subscribe to our e-newsletter below if you haven’t done so already to receive the latest updates from Sod University.