Bermudagrass

The South's main lawn grass and the South's worst garden weed, and it is the same plant. It creeps by runners above and below ground, roots at every node, and cannot be weeded out of a bed the way ordinary weeds can.

How it invades: a full-sun warm-season perennial that spreads by stolons above ground and rhizomes below, roots at every node, regrows from fragments, and creeps steadily outward from lawn edges into everything adjoining.

You will not be sowing this deliberately in a garden, so what matters is how it gets in and gets around.

It arrives three ways: as a lawn on the other side of a bed edge, in contaminated topsoil, mulch, or nursery pots, and on a mower deck. Seed matters least — most spread is vegetative.

It advances by creeping. Stolons run flat over the surface, through mulch, under weed fabric, across pavers, sometimes several feet in a season, rooting at every node. Rhizomes travel underground at four to six inches, deeper in loose or sandy soil, and come up on the far side of any barrier that does not go deep enough. Both are brittle, and every fragment with a node on it is a whole new plant. That single fact governs everything about control.

It is warm-season. It greens up when soil temperatures reach the 60s, grows hardest in the heat of midsummer when cool-season lawns are struggling, and goes fully dormant and straw-brown below about 50°F. Winter dormancy is not death; the runners are alive under the brown.

It demands full sun. This is its one real weakness. Bermudagrass thins in shade and disappears under dense shade, which is why it takes the hot strip along the driveway first and why it never quite conquers the bed under the maple.

Otherwise it is nearly unstoppable: it tolerates drought, heat, salt, traffic, poor soil, and close mowing, and it recovers from damage faster than any weed you will meet. Those are the exact traits that make it a great turf grass and an appalling neighbour.

Stolons, rhizomes, fragments, and seed - in that order of importance. Any node makes a new plant, which is why tilling multiplies it and why contaminated soil, mulch, and mower decks move it between properties.

Stolons do most of the visible work. They creep over the surface, root at each node, and colonise anything they can reach — through gravel, over mulch, along the join between paving slabs, up into a pot standing on the ground.

Rhizomes do the work you cannot see, moving through the soil at four to six inches and popping up beyond edgings, fabric, and plastic. This is why edging has to be deep to do anything and why bermudagrass reappears in the middle of a bed you thought you had cleared from the edge.

Fragments are the multiplier. A piece of stolon or rhizome with one node will root and grow. So a rotary tiller run through a bermudagrass patch is a propagation machine, and contaminated topsoil, mulch, and nursery stock are how it crosses town. Check the rootballs of anything you bring home from a southern nursery, and be sceptical of cheap bulk topsoil.

Seed matters least but is not nothing: common bermudagrass sets viable seed in those finger-like heads, and it can persist in soil for several years. Most hybrid turf bermudagrasses are sterile and spread only by runner — which is why they are sold as sod or sprigs rather than seed, and why a hybrid escaping into your beds behaves the same way as the common kind.

Control, not care: shade it out where you can, dig runners whole and never till, cut a deep edge, smother beds for a full hot summer, and use grass-selective herbicides in ornamental beds - repeatedly, over a season or two.

Set expectations first: an established patch takes a season or two to clear, and clearing a bed adjoining an infested lawn is permanent maintenance, not a one-time job. Nothing about this is quick, and anyone promising otherwise is selling something.

Cut a real edge. The highest-value structural fix. A spade-cut trench edge maintained annually, or solid edging set 6–8 inches deep, stops rhizomes from walking out of the lawn into the bed. Shallow decorative edging does nothing at all.

Dig, never till. Fork under the patch, lift the runners whole, shake the soil off, and bag them. Take your time following each stolon — leaving nodes behind is the reason people dig the same patch three years running. Never rototill bermudagrass; it turns one plant into hundreds.

Smother it, in summer. An empty bed can be cleared by covering it with heavy black plastic or a thick tarp through a full hot summer — six to ten weeks minimum, longer is better, and the heat is what does the work, so this is a June-to-September job in a sunny spot, not an April one. Clear plastic sealed at the edges (solarization) is more effective still in hot-summer climates. Cardboard and mulch alone will not do it; bermudagrass grows through both.

Shade it out. Mow cool-season lawns tall (3–4 in), plant beds densely so the soil is covered, and put the shade-tolerant plantings on the hot sunny margins where you are losing ground.

Herbicide, honestly. In an ornamental bed, grass-selective herbicides — the active ingredients fluazifop, sethoxydim, and clethodim — kill grasses without harming most broadleaf ornamentals, which makes them the practical tool for bermudagrass among shrubs and perennials. They need repeat applications, because rhizomes push new growth after each one. Non-selective glyphosate works on actively growing green foliage and also needs repeating. In a cool-season lawn there is no clean answer: the selective options only suppress it, and badly infested fescue or bluegrass usually has to be killed off and re-established. Whatever you use, three rules: the product’s label must list the site you are treating — vegetable garden, ornamental bed, lawn are all different sites and the label is legally binding — follow that label for rate, timing, protective equipment, and any interval before planting or harvest, and treat green, actively growing foliage, never dormant brown grass.

In a vegetable garden, far fewer products are labelled at all, so lean on the physical methods: deep edging, summer smothering, and patient digging.

Is it bermudagrass or crabgrass, why pulling fails, why tilling made it worse, what to do about a fescue lawn full of it, and how long clearing a bed really takes.

Is this bermudagrass or crabgrass? The commonest mix-up, because both make finger-like seed heads. Bermudagrass is a perennial with fine grey-green blades, a fringe of white hairs at the leaf collar, and both surface stolons and underground rhizomes; it comes back from runners every year. Crabgrass is an annual with wider, hairier, brighter green blades, sprawls in a star-shaped mat from a single crown, has no rhizomes, and dies at the first hard frost. If you pull it and a rope of runner comes up rooting at every joint, it is bermudagrass.

I pull it and it comes straight back. Pulling gets the shoot; the stolon and rhizome stay. You have to lift the runner whole, or exhaust the plant with repeated treatment.

I tilled the bed and now it is everywhere. Unfortunately that is exactly what tilling does — each chopped node becomes a plant. Do not till again; switch to summer smothering or repeated grass-selective treatment and dig out what you can whole.

It comes under my edging. Rhizomes travel four to six inches down and deeper in loose soil, so shallow edging is decorative only. Cut a spade-deep trench and maintain it, or set solid edging 6–8 inches deep.

It grows straight through my landscape fabric. It does. Fabric slows stolons a little and stops nothing below ground.

My fescue lawn is full of straw-brown patches in winter. That is bermudagrass, dormant while the cool-season grass stays green — and winter is the best time to map how far it has gone. There is no fully selective control in a cool-season lawn; suppression plus tall mowing helps, and a heavily infested lawn is usually killed off and re-established.

Can I just smother it with cardboard and mulch? No. It grows through both. Smothering has to be a heavy opaque cover for a full hot summer.

How long will clearing a bed take? A season or two of consistent work for an established patch, and ongoing edge maintenance forever if there is bermudagrass lawn next to it.

It is my lawn and I like it — is that a problem? Not at all; it is the right grass for a hot sunny southern lawn. Just treat the boundary between lawn and beds as a permanent job, and never plant a scrap of it near a vegetable garden.

Thrives roughly zones 7-11 and dominates the South and Southwest; in the transition zone it invades cool-season lawns; hard northern winters kill it, so it is barely a problem above about zone 6.

The South and Southwest (zones 8–11) are bermudagrass country. It is the default lawn, pasture, and sports-field grass, it grows nine months of the year, and in a garden it is a permanent management issue rather than a problem to be solved once. Deep edging and dense planting are not optional here.

The transition zone (roughly zone 7) is where it is most maddening, because cool-season and warm-season grasses both grow there. Bermudagrass creeps into fescue and bluegrass lawns and shows up as straw-brown patches all winter, and there is no herbicide that removes it cleanly from a cool-season lawn.

Zone 6 and colder is where winter does the work for you. Hard freezes without snow cover kill the rhizomes, so bermudagrass is patchy and short-lived in the north — it can arrive in contaminated soil or sod and persist for a season or two in a warm sheltered spot, but it does not establish the way it does south of the Ohio River.

Drought and heat make it stronger, not weaker. In a hot dry summer it takes ground from everything else in the garden, because the plants it is competing with slow down and it does not. That means late summer is when you lose the most territory — and, conveniently, also when a summer smothering treatment does its best work.

Brought from Africa to the American South by the mid-1700s and promoted as a pasture grass, it became the region's dominant turf and its most stubborn garden weed - and modern hybrids, which set no seed, spread the same way by runner.

Bermudagrass is not from Bermuda. It is native to eastern Africa and the warm Old World, and it reached the American colonies by way of the Caribbean — the name stuck from ships and cargo that came through Bermuda. It was recorded in the southern colonies by the mid-1700s and was being deliberately spread as a pasture grass soon after, because it does what southern farmers needed: it survives heat, drought, and hard grazing, and it repairs itself.

By the twentieth century it had become the defining turf of the American South — lawns, golf courses, athletic fields, roadsides — and the source of a good deal of southern hay. Plant breeders at Tifton, Georgia produced the famous hybrid turf types (the Tif- series and their descendants) by crossing it with African bermudagrass; those hybrids are sterile, which is why they are sold as sod and sprigs rather than seed, and why they spread by runner alone. In the garden that distinction changes nothing at all.

Its other name tells the rest of the story. Across the South it has been called ‘wiregrass’ and ‘devil’s grass’ for as long as people have tried to keep it out of vegetable rows — the same plant, praised and cursed, sometimes in the same afternoon by the same gardener.