Selectively killing Bermuda grass while leaving surrounding plants unharmed is possible, but the right approach depends entirely on what you’re trying to protect. In flower beds and broadleaf landscapes, grass-specific herbicides like fluazifop and sethoxydim can wipe out Bermuda without touching your shrubs or perennials. In cool-season lawns of fescue or bluegrass, a different set of chemicals exploits metabolic differences between warm-season and cool-season grasses. Each scenario calls for its own product, timing, and technique, and getting the match wrong can damage the plants you’re trying to save.
Why Bermuda Grass Demands a Targeted Strategy
Bermuda grass is one of the most aggressive turfgrasses on the planet. It spreads through both stolons (above-ground runners) and rhizomes (below-ground runners), meaning a single surviving node can regenerate an entire patch. The root system can extend more than six feet deep in favorable soil, and the plant goes dormant rather than dying in cold weather, coming back each spring from those deep reserves. A single pass with a non-selective herbicide like glyphosate will brown out what you see on the surface, but it often misses the rhizomes entirely, requiring multiple applications even when selectivity isn’t a concern.
This toughness is exactly why selective control matters. If you’re going to need repeated treatments regardless, you want a product that hits Bermuda hard while leaving your desirable plants alone. The selective options fall into three practical categories based on what you’re growing around the Bermuda: broadleaf plants, cool-season grasses, or warm-season grasses other than Bermuda.
Bermuda Grass in Flower Beds, Gardens, and Broadleaf Landscapes
When Bermuda grass invades flower beds, ground covers, or shrub borders, you have the widest range of selective tools available. A class of herbicides called ACCase inhibitors targets a fatty-acid-synthesis enzyme found exclusively in grasses (and a few other monocots), leaving broadleaf plants completely unaffected. These herbicides block a form of the enzyme that broadleaf plants simply don’t have, so roses, hostas, and ornamental shrubs shrug off the spray while the Bermuda grass starves itself of the lipids it needs to grow.1SciELO / Sci. agric. (Piracicaba, Braz.). Open-access ACCase-inhibiting herbicides: mechanism of action, resistance evolution and stewardship – Section: Mechanism of action (MoA)
The two most commonly available ACCase inhibitors for home landscapes are fluazifop-P-butyl (sold under names like Fusilade II and Ornamec) and sethoxydim (Segment, Vantage). Both are labeled for over-the-top application in ornamental beds, meaning you can spray directly over your flowers and shrubs. Fluazifop tends to be the more popular choice for Bermuda specifically because it provides slightly more consistent control on perennial warm-season grasses, but either product will work.
A few practical notes for this scenario:
- Expect repeat applications: Bermuda’s rhizome network stores enough energy to push new growth after the first spray. Two to three applications spaced about three to four weeks apart are typical before you see full control.
- Spray actively growing grass: Dormant Bermuda absorbs almost nothing through its leaf tissue. Wait until the grass is green and actively spreading, usually late spring through summer.
- Avoid drift onto desired grasses: ACCase inhibitors kill all grasses, not just Bermuda. If your flower bed borders a lawn you want to keep, use a shield or directed spray to prevent contact.
Bermuda Grass in Cool-Season Lawns
This is the scenario most homeowners find themselves in: Bermuda grass creeping into a fescue, bluegrass, or perennial ryegrass lawn, especially along sidewalks, driveways, and south-facing edges where summer heat gives Bermuda a competitive advantage. Here, the challenge is that both the weed and the lawn are grasses, so a blanket grass-killer would destroy everything. Fortunately, warm-season and cool-season grasses process certain herbicides differently enough that a few products can thread the needle.
Fenoxaprop-p-ethyl
Fenoxaprop (sold as Acclaim Extra) is another ACCase inhibitor, but unlike fluazifop, it can be used inside certain cool-season turf stands. Tall fescue and perennial ryegrass metabolize fenoxaprop quickly enough to survive applications that damage or kill Bermuda grass. Kentucky bluegrass is somewhat less tolerant, so rates and timing require more care in bluegrass-dominant lawns. Fenoxaprop is applied at low rates as a spot or broadcast treatment during Bermuda’s active growth period, typically requiring two or three rounds four to six weeks apart.
Topramezone
Topramezone (Pylex) works through an entirely different pathway. It belongs to the HPPD-inhibitor class, which disrupts pigment synthesis and causes treated plants to bleach white before dying. Cool-season grasses can tolerate topramezone at labeled rates, while Bermuda grass cannot recover from the pigment loss. Topramezone is often considered the strongest selective option for Bermuda removal in cool-season turf, but it’s a restricted-use product in some states and typically requires a pesticide applicator license to purchase. Homeowners often hire a lawn care company for this one.
Mesotrione
Mesotrione (Tenacity) is a related HPPD inhibitor available to homeowners. It will suppress Bermuda grass and bleach it white, but it generally doesn’t provide the same level of long-term control as topramezone on established Bermuda. It’s more useful as part of a renovation strategy, where you’re overseeding with new cool-season grass at the same time. Mesotrione suppresses the Bermuda long enough for the new seedlings to establish, giving the cool-season grass a head start.
In all cool-season lawn treatments, timing is critical. You want Bermuda actively growing (late spring through mid-summer) but ideally not during peak heat stress on your cool-season turf. Late May through mid-July in most transition-zone climates hits the sweet spot where Bermuda is fully active but fescue hasn’t yet entered its summer stress period.
Bermuda Grass in Zoysiagrass and Other Warm-Season Lawns
This is the hardest selective-control scenario. Both Bermuda and zoysiagrass are warm-season grasses, so their physiology is similar. Most herbicides that damage Bermuda will also damage zoysia, centipedegrass, or St. Augustinegrass. The options here are narrower, but research has identified a combination approach that works specifically for zoysiagrass lawns.
Fluazifop and fenoxaprop can suppress Bermuda grass in zoysia, but they also injure the zoysiagrass itself. However, when either product is tank-mixed with triclopyr (a broadleaf herbicide), the triclopyr acts as a safener for the zoysiagrass. Research has shown that adding triclopyr to fenoxaprop or fluazifop reduces injury to zoysiagrass without decreasing Bermuda suppression. In fact, the combination of triclopyr plus fenoxaprop actually improved Bermuda control compared to fenoxaprop alone.2Applied Turfgrass Science. Triclopyr Safens the Use of Fluazifop and Fenoxaprop on Zoysiagrass Maintaining Bermudagrass Suppression – Section: Abstract
The mechanism behind triclopyr’s safening effect isn’t fully understood, but the practical upshot is clear: if you have a zoysiagrass lawn with Bermuda creeping in, a tank mix of triclopyr plus fenoxaprop or fluazifop gives you a selective option that no single product offers alone. This combination is not commonly sold as a pre-mixed product, so you’ll likely need to buy the components separately and mix them at labeled rates. For centipedegrass and St. Augustinegrass lawns, the selective options are even more limited, and many turf professionals recommend a full renovation with non-selective herbicide followed by re-sodding rather than attempting selective removal.
Why Some Grasses Survive and Others Don’t
The selectivity of ACCase-inhibiting herbicides comes down to enzyme structure. The enzyme these products target exists in a form unique to grasses and other monocots, which is why broadleaf plants are completely immune. But even among grasses, sensitivity varies. Some grasses naturally produce forms of the enzyme that bind the herbicide differently, making them partially or fully resistant. Research on purified enzyme forms has found that insensitive versions of the enzyme display a cooperative binding pattern, meaning the herbicide molecules interact with each other at the binding site in a way that reduces overall toxicity, while sensitive forms lack this cooperative behavior.3Portland Press / Biochemical Journal. Graminicide insensitivity correlates with herbicide-binding co-operativity on acetyl-CoA carboxylase isoforms – Section: Abstract
In practical terms, this means that a cool-season grass like tall fescue can break down fenoxaprop quickly enough to survive a dose that slowly kills Bermuda. The herbicide isn’t ignoring the fescue; the fescue is simply processing and neutralizing it faster. This is also why application rates and timing matter so much. Push the rate too high or apply during heat stress when the cool-season grass’s metabolism slows down, and you’ll start injuring the lawn you’re trying to save.
How Adjuvants Change the Outcome
The herbicide itself is only part of the equation. What you mix it with can substantially change how much product actually enters the plant. Bermuda grass has relatively waxy, narrow leaf blades that shed spray droplets easily, so adding a surfactant or oil-based adjuvant to your spray solution improves absorption and, consequently, control.
Methylated seed oil (MSO) is one of the most effective adjuvants for grass herbicides. Research on HPPD-inhibiting herbicides showed that adding just 0.3% MSO to the spray solution boosted herbicide absorption by roughly 69% in grass weeds within 24 hours, which translated to about a 1.5-fold increase in overall weed control.4Europe PMC. The mechanism of methylated seed oil on enhancing biological efficacy of topramezone on weeds – Section: Abstract While that study was conducted on a different grass species, the principle applies broadly: MSO helps the herbicide penetrate the waxy cuticle layer that otherwise causes spray to bead up and roll off.
Non-ionic surfactants (NIS) are a milder alternative and are called for on many herbicide labels. They reduce the surface tension of spray droplets so the liquid spreads into a thin film on the leaf rather than sitting as a bead. For ACCase inhibitors like fluazifop, the label typically specifies either a crop oil concentrate or a non-ionic surfactant. For topramezone, MSO is the preferred adjuvant on most labels. Using the wrong adjuvant type, or skipping it entirely, is one of the most common reasons homeowners see poor results from a selective Bermuda treatment.
Timing, Repetition, and Realistic Expectations
No single application of any selective herbicide will eradicate an established Bermuda grass stand. The rhizome network stores carbohydrate reserves that can push new shoots for weeks after the above-ground growth has been killed. A realistic plan involves at least two and often three or four applications over a single growing season, spaced far enough apart for regrowth to emerge and produce enough leaf tissue to absorb the next treatment.
The ideal window for the first application is late spring, once Bermuda has broken dormancy and is actively producing new stolons. Bermuda that is still mostly brown or just starting to green up hasn’t generated enough leaf surface to absorb a lethal dose. Conversely, waiting until mid-summer means the rhizome reserves are at their peak, making control harder. Follow-up applications should happen every three to six weeks depending on the product, with the last application ideally occurring before early fall, when cool-season grasses need time to recover and fill in the gaps before winter.
Even with perfect chemical timing, Bermuda can persist in areas with full sun and warm soil. If your cool-season lawn borders a neighbor’s Bermuda lawn or a public right-of-way, reinfestation is almost guaranteed. In those situations, a physical barrier like deep edging (at least four to six inches) along property lines can slow the stolons, though rhizomes can eventually travel under any shallow barrier.
Non-Chemical and Cultural Approaches
For gardeners who want to avoid herbicides, or who need a complementary strategy alongside chemical treatment, several cultural methods can suppress or kill Bermuda grass with varying degrees of effectiveness.
- Solarization: Covering the infested area with clear plastic sheeting during the hottest months (June through August in most regions) traps heat and can raise soil temperatures high enough to kill rhizomes in the top several inches. This works best in full-sun areas and typically requires six to eight weeks of continuous coverage. It will kill everything underneath, so it’s a reset strategy rather than a selective one.
- Sheet mulching: Layering cardboard or thick newspaper over the Bermuda, then covering with several inches of mulch, blocks light and physically smothers the grass. It’s slower than solarization and may take an entire season to fully kill deep rhizomes, but it simultaneously builds soil organic matter as the cardboard decomposes.
- Aggressive overseeding: In cool-season lawns, thickening the stand by overseeding heavily every fall creates competition that slows Bermuda’s spread. A dense fescue or bluegrass canopy shades the soil surface, which Bermuda needs for stolon establishment. This won’t eliminate Bermuda, but it can keep it from dominating.
- Mowing height: Keeping your cool-season lawn at the tall end of its recommended mowing height (3.5 to 4 inches for tall fescue, for example) shades out Bermuda, which thrives at lower mowing heights. Bermuda maintained at its preferred half-inch to one-inch height in full sun is almost unstoppable, but Bermuda struggling under the shade of four-inch fescue grows slowly and is more vulnerable to herbicide treatment.
These methods work best in combination. A homeowner dealing with a moderate Bermuda invasion in a fescue lawn might raise the mowing height, overseed aggressively in fall, and spot-treat breakthrough Bermuda patches with fenoxaprop or topramezone in early summer. That three-pronged approach reduces the chemical load while exploiting Bermuda’s weaknesses.
When Selective Control Isn’t Worth the Effort
Selective Bermuda control works well when the infestation is patchy: isolated runners along a driveway, a few stolons creeping into a flower bed, or scattered clumps in an otherwise healthy cool-season lawn. But when Bermuda grass constitutes more than roughly a third of the total turf area, the math changes. You’ll need so many repeat applications over such a large area that the cost in herbicide, time, and turf stress often exceeds the cost of a full lawn renovation.
A renovation typically means applying a non-selective herbicide (glyphosate or glufosinate) to kill everything, waiting the labeled re-entry period, and then re-sodding or seeding the desired grass. In warm-season zones where Bermuda is the dominant turf species and homeowners actually want it, the problem is usually reversed: other grasses invading the Bermuda. But in the transition zone, where cool-season and warm-season species overlap geographically, Bermuda is the classic uninvited guest. Homeowners in these areas, stretching roughly from central Virginia through Tennessee, northern Georgia, Arkansas, and into Oklahoma, deal with Bermuda invasion as a recurring seasonal challenge rather than a one-time fix.
If you’re in that zone and the Bermuda keeps returning despite repeated selective treatments, it may be worth considering whether the site conditions (full sun, south-facing slope, clay soil that holds summer heat) simply favor Bermuda over your preferred grass. In those cases, the most permanent solution might be accepting Bermuda in that section and managing it as intended turf, or installing a hard border and planting non-turf ground cover that can be maintained with occasional fluazifop applications to keep the Bermuda from jumping the line.