One of the constant challenges of lawn maintenance is dealing with invasions of unwanted grass species. Bermuda grass is a tough one, because it’s aggressive and very quickly spreads both above and below ground to take over lawns and planting beds.
You may have patches of wild Bermuda grass (sometimes called wire grass), or you may be dealing with an invasion from a neighbor’s cultivated Bermuda lawn. Here are some tips for dealing with unwanted Bermuda grass in your lawn.
Natural Approach
Rather than resorting to chemicals to solve the problem, try using Bermuda’s natural traits against it while encouraging the growth of your lawn grass at the same time:
- Increase Shade: Bermuda grass requires a lot of sunshine. Set your mower height to 3-4 inches, and your taller lawn grass will shade out the Bermuda. This is probably the most effective strategy even though it takes time. (On the other hand, if you want to keep the Bermuda and get rid of other grasses, set your mower blade low, and the Bermuda will eventually win out).
- Limit Fertilizer: Bermuda also needs more fertilizer than other types of lawn grasses, so you can discourage its growth by reducing applications of fertilizer. For cool-season lawns, limit fertilizing to the fall, after the Bermuda has been nipped by frost.
- Encourage Preferred Grass: A healthy lawn is always more resistant to invasion. Learn about your particular lawn grass, and take steps necessary to encourage a thick turf that is resistant to weeds and other grasses.
Chemical Solution
If you decide to resort to using chemicals to control the spread of Bermuda, how you go about it will vary depending on the type of grass (or other plants) the Bermuda is invading:
- Cool-Season Grasses: If you have a cool-season lawn (fescue, bluegrass, or rye grass) you can use a product such as Bayer Bermuda Grass Control to kill Bermuda without harming your lawn.
- Warm-Season Grasses: Since Bermuda is a warm-season grass, chemicals that are used to control it will also kill other warm-season grasses—including St. Augustine, zoysia, and centipede. A total vegetation herbicide, such as Roundup (glyphosphate), can be used to kill ALL the grass—including your existing lawn. Then once you are rid of the invading Bermuda grass, you would need to replant your lawn with your favorite turf grass.
- Around Shrubs and Trees: There are products, such as Ornamec or Grass Getter, which are designed to kill unwanted grasses without harming shrubs and trees.
Keep in mind that ALL herbicides contain chemicals that upset the ecosystem (that’s what they’re designed to do!), and many contain ingredients that are toxic to humans and animals. I always recommend using them only as a last resort.
Further Information
- Stamp Out Bermuda Grass (Bay Weekly)
- Bermudagrass Control (Utah State Extension, PDF 161kb)
- How to Control Weeds in Your Lawn
Wild bermuda can be killed but not without collateral grass death. The bestway to control it in St Augustine is the use of pre emerent. Wild bermuda is a seed that grows long roots but goes into some form of winter dormacy. Use the pre emergent early spring..mid feb to march then again 60 days later…you may need to do it longer. Pre emergent basically chemically coats the seed preventing germination. Thiswill alslo slow down crabgrass and carpetweed germination.
The St Augustine will limit the bermuda in time….good luck
If St Augustine will limit the Bermuda in time, Then how was it able to overtake it in the first place?
I replaced a large section of St. Augustine lawn last year due to a large infestation of wild bermuda. I dug up the lawn, put weed and grass killer on the area three different times and then put sand and resodded. This year I am again being bombared with wild bermuda. HELP!!
I’m in Houston, Texas. I have a small patch of St. Augustine growing between the street & sidewalk that my sprinkler doesn’t reach, so I have to hand water it. Due to a bit of neglect on my part, some of it has died and Bermuda is taking over which is fine with me since I won’t have to water it as much by hand in extreme temps. What can I do to encourage the Bermuda to take over just in this one small patch? I’m thinking I might just try to pull the St. Augustine out and leave the Bermuda to spread. Any advice will be appreciated. Thanks!