* Never use any weed product on a turfgrass unless the grass is noted on the product’s label.
For an inside look at how relentless weeds outmaneuver many homeowners, consider yellow nutsedge. The bane of homeowners and landscape professionals alike, this tough perennial weed resists all comers. Despite its grasslike leaves and common name of nutgrass, yellow nutsedge isn’t a grass at all. It’s not a broadleaf weed either — it’s a sedge. Common weedgrass killers and broadleaf weed killers, which work on most lawn weeds, are ineffective against this opponent.
Try to dig or pull any of these tough lawn weeds out and you’ll usually aid their cause, leaving rhizomes, nutlets or taproot bits to multiply and grow. They’ll even hitch a ride on your gardening tools to get to a new location.
Meeting the Challenge
IMAGE All-in-One Weed Killer’s dual-action attack works through both leaves and roots to control problem weedgrasses, sedges and broadleaf weeds, with visible results in less than 24 hours.
A warm-season weed, nutsedge stays active during summer and often outgrows cool-season lawn grasses. It quiets down and dies back as temperatures drop in the fall, but the nutlets and rhizomes, which are a foot or more below the surface, stay protected, even in northern climates. In spring, tubers send up new shoots, which form new nutlets in six weeks or less. Before you know it, a 6-foot patch of nutsedge is out-competing your turf grass.
Nutsedge spreads by seeds and underground stems known as rhizomes, but its primary route for turf takeovers is its underground tubers, known as nutlets. Nutlets store energy reserves and bear buds, sort of like potatoes do, and send up sprouts to form new plants. Penn State Extension reports that one year’s worth of rhizome growth from a single nutsedge tuber can produce 1,900 plants with 7,000 new tubers. A single plant can produce 90,000 seeds in one season. 1
*Always read product labels thoroughly and follow instructions, including guidelines for specific lawn grass types and weeds.
Nutsedge makes itself known during periods of rapid summer growth as it outcompetes heat-challenged lawn grasses for water and nutrients. The bright yellow-green leaves of yellow nutsedge stand out clearly against turf, as do the dark green leaves of its purple relative. Left to grow tall, nutsedges produce distinctive spiky flower clusters: yellow-brown for yellow nutsedge and purple-brown for purple nutsedge.
Nutlets formed below ground stay viable for many years.
Controlling Yellow and Purple Nutsedge Effectively
By practicing good lawn care basics, you can protect against nutsedge invasions and give your grass an advantage over these aggressive weed pests. Healthy, vigorous grass is an excellent defense against yellow and purple nutsedge in lawns.
Nutsedge outbreaks often start in moist, poorly drained lawn areas, where they quickly develop into large colonies. Their extensive root systems may reach up to 4 feet deep. 1 Once established, these weeds can tolerate drought.
The key identifying feature for these difficult weeds is their triangular stems. Roll the stems between your fingers, and you’ll understand the meaning of the old-time rhyme “sedges have edges.” In contrast, grasses have round stems. Shiny, smooth nutsedge leaves have a distinct center rib and form a “V” shape.
For established cool-season lawn grasses, such as Kentucky bluegrass, tall and fine fescues, perennial ryegrass and rough bluegrass, IMAGE All-In-One Lawn Weed Killer begins working on contact to kill and control existing nutsedge. This convenient, ready-to-spray product provides visible results in three to seven days and kills yellow nutsedge within two to three weeks. Purple nutsedge may need repeat treatment every three to four weeks for effective control.