Centipede grass is a warm-season grass variety that forms beautiful, lush green turf when it’s healthy. However, its health and appearance can greatly diminish when it’s invaded by common lawn weeds. To stop weeds from taking over your Centipede grass turf, you need to apply a selective post-emergent herbicide.
Altizine and Trimec are some of the top suggestions for effective weed killers for Centipede Grass. They are some of the herbicides that work on a wide range of annual broadleaf weeds.
6 Best weed killer for centipede grass
The most effective and safest herbicides for centipede grass are selective herbicides that target only the weeds without harming the desirable turf grass. Some of the best post and pre-emergent weed killer for centipede includes; Mecoprop, Dicamba, Halosulfuron, Sulfosulfuron, Sethoxydim, and Prodiamine.
1. Mecoprop (MCPP)
Mecoprop is a herbicide commonly used to control both annual and perennial broadleaf weeds in centipede grass lawns. Examples of weeds that are highly susceptible to this herbicide include clover, mouse-eared chickweed, and common chickweed.
Mecoprop is a chlorophenoxy herbicide that works by disrupting the movement of nutrients through the plant, thereby causing plant death. Unlike many other selective post-emergent that can cause damage to young turfs, Mecoprop is safe for use on both established centipede turfs and centipede seedlings.
Note: Despite readily leaching in soil, Mecoprop has reduced environmental effects. Tt biodegrades in a relatively short time.
Dicamba is a selective, post-emergent weed killer that effectively controls a wide variety of broadleaf weeds and woody plants. It works by mimicking naturally-occurring auxins in weed plants, thereby disrupting cell division and normal plant growth.
Dicamba is commonly mixed with other herbicides like 2, 4-D, and Mecoprop to form a herbicide mix. Examples of dicamba-based weed killer products include CELCIUS WG herbicide by Bayer and Spectracide Weed Stop for Lawns.
Note: One major downside to using dicamba as a weed killer on centipede turfs is that it tends to drift to unwanted areas such as the flower garden or the natural hedge fence, killing desirable ornamental plants in these parts of the yard as well.
Controlling sedge weeds/nutgrass invasion in centipede grass can be quite difficult as they’re neither grassy weeds nor broadleaves. Halosulfuron is a herbicide that selectively kills sedges. The recommended application rate for Halosulfuron is 1½ lbs. per acre. If the sedge weed invasion is severe, a repeat application may be necessary after 6-10 weeks.
A well-known Halosulfuron-based herbicide product is Sedgehammer (75DF). Sedgehammer effectively controls common centipede grass sedge weeds such as yellow nutsedge and purple nutsedge.
Note: Halosulfuron-based herbicides like Sedgehammer work slowly. Even though they immediately stop weed growth, it typically takes up to 3 weeks for the sedges to start dying.
Sulfosulfuron is a selective, post-emergent herbicide used to control sedge weeds and to suppress grassy weeds on centipede grass, such as rough stalk bluegrass and annual bluegrass. This herbicide works best if applied at a rate of 0.75-1.25 lbs. per acre. A repeat application is recommended after 4-10 weeks if the target weeds don’t completely die the first time.
Sulfosulfuron is relatively eco-friendly due to its minimal residual soil activity. In fact, its half-life in soil is 1-6 weeks. The most notable Sulfosulfuron-based herbicide is Certainty (75DF), with the active ingredient forming 75% of the product formulation.
While most selective weed killers only kill broadleaf weeds, Sethoxydim selectively kills grassy weeds. Use it to get rid of crabgrass and goosegrass, without doing much damage to your centipede grass turf.
Beware, though. Depending on the health of your centipede turf, grass yellowing may occur after applying Sethoxydim. Still, this shouldn’t be much cause for concern as the grass recovers soon after. Examples of brand products with Sethoxydim as the active herbicide ingredient include Hi-Yield Grass Killer and Ferti-lome Over the Top Grass Killer.
Note: While it’s totally safe for use on mature centipede turfs, you should only use Sethoxydim on a newly-planted Centipede Grass lawn if the stolon growth has reached at least 3 inches.
Prodiamine is the only pre-emergent herbicide on this list. While post-emergent weed killers effectively control actively growing weeds, they have no effect on weed seeds harbored in the ground. Consequently, the weed seeds can still germinate and form new weed growth down the line.
You need a powerful pre-emergent herbicide like Prodiamine to suppress the germination of weed seeds. Lightly water the lawn post-application and again after two weeks to activate this herbicide.
Note: Prodiamine is best reserved for well-established Centipede turfs as it can also kill young Centipede grass that’s still shallow-rooted.
Can I use herbicides on my centipede grass lawn?
You can use herbicides on your centipede grass lawn. A weed-free centipede lawn grows healthier as it doesn’t have to compete for water and nutrients with invasive plants. While you can use herbicides on your centipede grass lawn, the real secret lies in knowing which weed-killers you can safely use and which ones to avoid.
The safest herbicides for centipede lawns are selective post-emergent herbicides like the ones detailed in the previous section. Weed and feed products that combine selective herbicide and fertilizer ingredients are also great as they kill weeds while feeding the lawn at the same time.
Note: Non-selective post-emergents like Glyphosate (Roundup) and Glufosinate will kill actively growing centipede grass and should only be used if the turf is dormant.
Can you spray Roundup on dormant Centipede?
You can safely spray Roundup to get rid of actively growing weeds on a dormant centipede lawn. Cool-season weeds typically thrive on Centipede lawns in the winter while the turf grass is in dormancy. And since dormant grass can’t take in systemic weed killers such as Roundup, you can use such herbicides to control winter weeds on dormant centipede grass.
The active ingredient in Roundup is glyphosate, a non-selective systemic herbicide that will quickly kill your desirable centipede grass if it’s actively growing. However, during dormancy, the brown centipede grass leaves won’t absorb the herbicide, thus escaping harm before greening up again the next spring. And even though the grass roots are still alive during dormancy, they remain unaffected as there’s no way for the Roundup to be absorbed and translocated.
Note: A brown lawn doesn’t always mean that the grass is dormant. In the case of centipede grass, you may still have green growth in the form of stolons below the brown grass blades. Applying Roundup to this kind of turf will kill the stolons, leaving no chance for turf grass recovery.
Will 2, 4-D kill centipede grass?
2, 4-D will not kill centipede grass as it’s a selective systemic herbicide. Selective herbicides are formulated to kill only a specific type of plant, such as broadleaves. For instance, 2, 4-D works by inhibiting growth processes found in broadleaves but not turf grasses.
2, 4-D enters weed plants through the leaves and shoots before being translocated to the rest of the plant, including the roots. This herbicide mimics a naturally occurring plant chemical, resulting in a chemical imbalance and eventually killing the whole weed plant. 2, 4-D is one of the most commonly used herbicides for killing broadleaf weeds without harming the turf grass.
Some brand products contain a herbicide mix of 2, 4-D alongside other selective, post-emergent like Mecoprop and Dicamba. Such herbicide mixtures are usually more effective at controlling weeds in centipede grass. Ace Lawn Weed Killer, Weed-B-Gon Ready Spray, and 33 Plus are common examples of brand herbicide products with a herbicide mixture that includes 2, 4-D.
Even though 2, 4-D doesn’t kill centipede grass, it has the potential to cause temporary turf injury whereby the grass blades may turn yellow. This is more likely to happen if the herbicide isn’t applied at the recommended rates, or if the air temperatures rise above 85° F a day after application.
Read More: What Weeds Does 2,4-D Kill in Lawn?
Note: To prevent the potential for centipede grass turf injury when using a 2, 4-D-based weed killer, low application rates are recommended. Also, check the weather forecast to ensure that temperatures will stay below 85° F for at least 24 hours post-application.
Is atrazine safe for centipede grass?
Atrazine is a herbicide that works both as a pre-emergent and post-emergent. It can, therefore safely be used on actively growing centipede grass as a selective post-emergent weed killer.
Some of the common weeds that Atrazine effectively controls are ragweed, pigweed, and lamb’s quarters. You can mix this herbicide with agricultural oil and water to boost its weed-killing power.
i. Daniel J. Leonard, University of Florida- Institute of Food and Agricultural Sciences (IFAS) Extension: Centipede Grass Weed Control: You Only Need 3 Herbicides!
ii. University of Georgia Extension: Weed Control in Home Lawns