Dear Ruth,
I have Bermuda grass in my yard and it is getting into my garden beds. NOTHING I have tried has worked to get rid of it. What do you suggest?.
Thanks,
Joan — Flat Rock, NC
Dear Joan,
This question is close to my heart. I bought a house a couple of years ago, and the yard is filled—FILLED—with Bermuda grass that the former owner must have purposely seeded into the lawn. For me, Bermuda grass presents a mind-boggling obstacle to pleasurable gardening. Bermuda grass laughs at your thorough weeding job and respects no boundaries. It quickly and ceaselessly overtakes your garden beds without any regard for your prospective harvest. Once you have planted, it is nearly impossible to weed it out without destroying your veggies and flowers.
Although Bermuda grass (Cynodon dactylon) is considered an excellent pasture grass, it is a gardener’s nightmare. This highly invasive grass originated in the eastern hemisphere, was once promoted by the USDA as a high-value forage crop and lawngrass, and is now prevalent in the southeastern and southwestern USA. Bermuda grass is also called wiregrass, couch grass, and devil’s grass (very appropriate nickname!) It reproduces in three ways—by seed, by above-ground vine-like shoots (stolons), and by below-ground shoots (rhizomes). Seeds remain viable in the ground for a couple of years. It is extremely difficult to kill even with multiple applications of strong herbicides.
Gardener Alert
Adjectives in my research described Bermuda grass as evil and tenacious with roots that “go to China.” Texas garden designer Liz Klein likened it to “tiny running bamboo.” It is very devious and sneaks its way into your yard by growing in difficult-to-reach spots—alongside the foundation of your house, mixed into the iris bulbs, and along rock borders. It rebounds at an astonishing rate, and grows straight across your paved driveway without missing a beat.
I have re-weeded areas multiple times, digging down as deep as I could looking for rhizomes, and the grass returned and spread like wildfire, even growing vertically into small shrubs. I have edged my driveway to find 3-foot-long stolons leaping across the pavement 30 days later.
Best Solution
Prevent the grass from achieving photosynthesis by covering it with a barrier. Plain mulch is not adequate to suppress Bermuda grass. In my yard, I used sheet mulching effectively with the long-term plan of doing my entire yard over time.
MATERIALS NEEDED
- Compost
- Cardboard
- Sod Staples
- Mulch
STEPS
- Mow or (better yet) weed-eat the grass area as low as possible, ideally to the ground. Then rake up and remove any grass/rhizomes/stolons.
- Lay down a half-inch layer of compost over the entire area. This will stimulate biological activity.
- Flatten cardboard boxes and leave them together so they will be two layers thick. Appliance boxes are ideal.
- Lay cardboard over the entire area, overlapping box edges at least 6 inches so there is no place for grass to grow through.
- Secure cardboard with a generous number of Sod Staples to help prevent grass penetration.
- Thoroughly wet cardboard all the way through—this is important.
- Cover area with 3 inches of mulch.
- Do NOT allow Bermuda grass to grow on top of mulch. Weed-eat it back.
- Do NOT cut holes in cardboard for planting as that will be a spot that the Bermuda grass could take hold.
- If a seedling pops up weed it out quickly.
- Allow 4–6 months or more before disturbing the area.
- In already planted areas, consider removing the existing plants to a temporary bed during this process. Otherwise it is likely that Bermuda grass will thrive at the base of the existing plants and re-invade your garden bed.
Other Thoughts
- Be extremely vigilant. Learn what Bermuda grass looks like, and do not import any plant material into your yard that contains even a hint of Bermuda grass. It’s not worth it.
- Edge and weed-eat regularly to keep the Bermuda grass confined to the lawn and OUT of your garden beds. If the grass is not yet in your beds, this can be a very effective remedy if done religiously.
- Do not rototill the area. You will break the rhizomes up into small pieces that will create more plants.
- One application of RoundUp (or other herbicide) + ground cloth is not considered a viable long-term solution. Vinegar-based sprays and organic herbicides like BurnOut may temporarily suppress Bermuda grass.
- If you already have Bermuda grass, be aware that eradication is an ongoing and probably a multi-year challenge (Matt Martin, using a very strong herbicide, considered it a 3–4 year endeavor).
- YouTube gardener EcoTechnify found old carpet very useful for suppressing Bermuda grass. He lifted the edges twice a year to keep the grass from growing over the top.
- During the heat of summer when the grass is most actively growing, solarize the area using UV clear plastic adding 2 feet to the area on all sides for good measure. Allow 6 weeks to work.
- When digging out Bermuda grass rhizomes, gardener David Stillwell put the soil through a screen to capture smaller rhizomes.
- Do NOT add any part of Bermuda grass to your compost pile or leave it in your yard. It needs zero encouragement to re-take your yard.
- Manures should be composted to the proper heat to kill any Bermuda grass seeds before applying to your garden.
- Check out University of California’s Integrated Pest Management Information.
Readers, if you have a solution that has proved effective for a minimum of one year, please share! And Joan, I sincerely wish you great success with this job.
Thanks for writing,
Ruth
Ask Ruth © 2018 Ruth Gonzalez & Organic Growers School
Author: Ruth Gonzalez
Ruth Gonzalez is a former market farmer, gardener, and local food advocate who wants to see organic farms proliferate and organic gardens in every yard. She serves on the Organic Growers School Board of Directors, and in her job at Reems Creek Nursery, Ruth offers advice on all sorts of gardening questions, and benefits daily from the wisdom of local gardeners.
When I moved to my place 12 years ago one of my neighbors told me that my place had been worked hard by a previous owner…. lots of inputs and lots of yield. He said, “ only problem is that girl, you have yourself some Bermuda”. After years of regeneration, I still have some Bermuda… major amounts. All that weeding, all that digging, all that burning, all that feeding to goats…. has not seemed to make much of an overall dent. The only beat back that I have found is to do the heavy cardboard layers that extend beyond the perimeters of a planned raised bed, build the raised bed, fill with soil that has been made in the compost/chicken yard, mulch HEAVILY around the perimeter of the bed…extending over the layer of cardboard and then pull all the runners that seem to “come up for air” around the cardboard. Any plantings that are out in the open and not in beds are just frequently weeded with the abandonment of any idea of ultimate completion of the task. I have heard of and plan to try at some point the concept of digging a 6 inch wide trench around landscape beds and filling the trench with gravel. Then, plant within the trenched area. Has anyone tried this? Best of luck to us all. On a positive note, the rhizomes seem to make a very effective treatment for kidney stones when dried and made in to tea.
Ruth, great article, I recognize your passion on this subject.
I’ve spent more of my energies fighting another garden invader, mugwort, but I have Bermuda grass in the lawn and am engaged in an ongoing battle at the borders. I actually find it emotionally therapeutic when I’m stressed out to dig Bermuda grass roots after rain and the ground has been softened so I can go deep. When I wish to convert another patch of lawn to garden, I’ve had success overlapping, by a foot or so, large scraps of metal roofing remaining from my last roof job some years ago, leaving them in place 3-6 months, held in place by stones. It is important not to walk on them when it rains, as they get very slippery, and the edges are crazy sharp and must be handled with tough gloves. I’m also careful to anchor them down sufficiently during and between uses to keep them from blowing in big winds.
On a farm scale till or disc multiple times in spring over a one month period preferably during a drought or period of little rain when the bermudagrass normally emerges. Final tillage should be shallow and done as soon as the soil is barely dry enough to do the tillage after a rain. Then plant a cover crop of sudex and cowpeas into moisture at a high rate. Mow the cover crop to 12” every time it reaches 4’ all through summer. Mow to ground in September then till and plant a winter cover crop of ryegrass. Bermudagrass should be gone the next year.
Hi Shawn! Love the idea. It is hard to imagine a cover crop of any kind out-competing Bermuda grass. May I inquire whether you yourself have accomplished this successfully on property you have lived on for at least 2 1/2 to 3 years after the “treatment”? Bermuda grass seeds are viable for 2 years in the ground. Also curious about the amount of Bermuda grass you were dealing with. Was it pasture planted in Bermuda grass?
Hi Ellen! I like the idea of using metal roofing. That should have similar results as the cardboard or the carpet.
I love that you find weeding Bermuda grass therapeutic. I wish I could have that attitude. For me it is the opposite of therapeutic. At the beginning I thought my thorough weeding job was sufficient. Nope. Just a temporary setback for mean ole Bermuda grass! It is in every part of my yard, and after re-weeding the same area multiple times without any permanent result, it puts a serious damper on my gardening plans.
Hi Alisa! I feel your pain since I am in a similar situation. As far as the gravel barrier, I suspect the Bermuda grass will grow right through the gravel – just as easily as it grows halfway across my concrete driveway. And the gravel will just make it harder to weed out because you can’t dig through gravel. Maybe you should give the carpet idea a try…here is the link: https://www.youtube.com/watch?v=YMSYB7XOthk
Key thoughts: Bermuda grass doesn’t like shade, it likes sunshine. So anything we can do to create shade ie. cardboard, carpet, Ellen’s metal roofing (see below) should be somewhat helpful. And I think you would have to raise the carpet every 1-2 weeks to keep the Bermuda grass from jumping across the carpet (not twice a season like he mentions in the video).
Did the cover crop work?
Would love to know as we have bought a house to rennovate where the “garden” is really three acreas of rough land and forgotten beds that has been left for decades. It is along a woodland edge (also ours), with farmland/ sheep either side. The garden/grassland has only ever been mown, (so no beds beds now…you can just find stones where a couple of flower beds once were). The scale means we often let some areas of grass grow to about six inches to a foot. The land is uneven, some sloping, bramble, lots of couch grass,creeping buttercup, loads of dock, thistle etc. (Also just to make life difficult some lovely primroses!) We would like to cultivate it/ design a garden, make some flower beds, veg and fuit gardn, but don’t feel we can start until we get rid of the field weeds. …they are so strong and fast growing, they would quickly gobble up anything we put in. Would a cover crop be a good way to start when working on this scale? Would you recommend pesticides….ie is it possible to do this organically? Any tips would be wonderful:-) We also get deer and ticks….so would like to dissuade those as well. Prepared to take the long, patient road if one day I can have a garden free of these pesky bullies!
Hi Liz,
I have not personally tried cover-cropping as a way to squeeze out Bermuda grass (couch grass), but my gut instinct is that cover cropping by itself would not be successful (if others have accomplished this successfully, please speak up!). Bermuda grass is stronger than most cover crops and that is why one of its nicknames is Devil Grass. I think cover-cropping would be successful in areas that do not have Bermuda grass.
I would re-read the ideas in the above article and make an action plan to retake a small area of your property. Leave sheet mulch or carpet down 4-6 months minimum and confirm with your eyes whether the Bermuda grass is dead before planting anything, I like the idea of using carpet as a more “permanent” barrier around the border of the new garden area – even though it is ugly. Keep the surrounding area mowed and all weeds cut back before they set seed. Weed-eating the perimeter of your area weekly would be extremely helpful in keeping the Bermuda grass outside your potential garden area. Herbicide usage is addressed in the article, and some herbicides are even stronger than Roundup. Even with herbicides, it is still tough to kill Bermuda grass. I personally have not had the heart to use Roundup. Regular mowing will help reduce tick habitat. Deer prevention usually requires a really good fence (goggle deer fencing), but there are some OMRI-Approved Deer Repellents like DeFence(TM) by Havahart and Plantskydd(R) Repellent that some gardeners find successful. Start small and do well maintaining that area before enlarging your garden area. Best of luck! – Ruth
Thanks Ruth, much appreciated. I will have to put a local small ad up for old carpets:-)
I honestly feel that only a 8 week period of dolarization with 2 mm Uv clear plastic will eradicate the devil grass in my garden area. So I am doing that now between my raised beds and a 2 foot area all around. There will be no tilling just a good a good taking and cardboard layer down for new additional garden beds going in fall of 2018. But once solarized wondering if I can put down 20 year premium landscaped barrier fabric and landscape timbers and about 4 inches of pea gravel in between and around beds with landscape timbers holding it in, or will it be a constant spray kill scenario?
I’m in Phoenix. I started my solarization with 2mm clear in June, an left it 3 months through the end of August. Plastic over the edges of the raise beds, draped down to the ground, held in place with logs & stones. Bermuda started to sprout again almost immediately after I removed the plastic and watered the soil. I’m thinking maybe next summer I’ll dig out a hollow in the middle of the garden beds, pack with dead wood and start a bonfire.
I want to plant an herb garden in an area of my mother in laws back yard in Phoenix as-it’s currently covered in long grass and Bermuda grass. Do I need to wait the 6 months before I start actually topping it with soil and planting? If I wait too long to weed it’ll be too hot for outside work and if I wait too long to seed, it’ll be too hot for the new plants to grow? Am I looking at a longer plan than I thought? Originally I was hoping to start planting in late winter/early spring. Any suggestions? Thanks for the great article!
Cardboard and mulch is effective….. temporarily. As soon The cardboard has completely decomposed Bermuda will start creeping in from the borders again. Ugh! I hate Bermuda!!!!
The only thing I have found that is effective is to first create a barrier. Dig a trench 2 feet deep around your garden area, fill it with concrete and pour a 3 foot sidewalk around that. This creates an effective barrier against Bermuda as long as you weed eat the sidewalk. We are doing this for a vegetable garden area. For a smaller flower bed you can also dig a trench, and build up a wall 6 inches on top of the trench. This can be a concrete wall, brick and mortar or limestone and mortar. You must use mortar, or Bermuda will sneak through the cracks if you don’t. You still need to weed eat religiously because the Bermuda quickly climbs over the 6 inches, but this has proven to be effective for several years.
I know, I know, it sounds like a lot of work and it is expensive, but i have tried everything. This it is the ONLY long-term solution if you have Bermuda on your property.
Great post. As we are planning to lay our new turf in our backyard, our turf supplier recommends Sapphire Buffalo grass for our yard which is best to grow in both shade and sunlight with less maintenance, I prefer Sapphire Buffalo turf. Here I got ideas of Bermuda turf to use for the various purpose and soil types. Thanks for Sharing.
I happened upon this article in an effort to make sure this stuff never comes back!!! We just sod cut our entire front yard because it was so choked with bermuda grass (in Northern Utah where it’s considered an invasive weed). It was so bad in parts that it actually choked out the sod cutter, which was at full depth. Now, I’m working on the edges and tearing anything else up before we go back to laying down fresh sod and planting flowers around the edge of our property.
Thanks for the this advice!
I have thoroughly enjoyed reading what everyone has been saying about getting rid if couch grass, or Bermuda grass as you call it over here. I was brought up in UK where I learnt much of what I know about gardening, and couch grass was always a potential bugbear over there. However, as far as I know it was never planted in lawns deliberately so I am appalled to learn that that happens here in California. I don’t have the luxury of having my own garden nowadays, but in between travels I do have the pleasure of helping my son with his garden – unfortunately he hasn’t totally inherited his Dad’s enthusiasm for gardening and would rather be out surfing or on the beach with the my grandkids. My initial project was to help build a couple of raised beds for vegetables and our first effort was a disaster – the couch grass just laughed at the cardboard mat we placed under the beds . So this year I have deep dug the complete area tearing out every scrap of couch grass and sieving as much of the soil as possible to remove all traces of the rhizomes, rebuilt the raised beds with an inner lining of that black cloth that allows moisture in but supposedly will keep weeds out – we’ll see if that works next year! I also created a wooden border along the edge of the nearby lawn and am pleased to see that the couch grass doesn’t seem to want to go under it and only wants to send out those damned tendrils over it which, if I catch them quick enough, are fairly easy to nip off before they take hold on the other side. So now that I also have been given the keys to the lawn mower (!!) I am continuing the fight into the rest of the garden. The coronavirus pandemic has prevented travel and given me more time in the garden this year, so there are some benefits from it I guess!!
Cardboard and mulch – my bermuda grass seems to like the extra ‘fertilizer’ – it grows under, over, and through it.
One thing that has been effective: I installed two rain gardens. Dug out the top layer of soil completely and removed it to a different area. The rain garden hasn’t seemed to have the problem with bermuda since, except along the very edges. But I don’t think it was the digging. I think it was the extreme moisture. I’ve found some things that sort of look like rotted bermuda rhizomes at times. So… can you drown bermuda? If so, I’d gladly flood the whole yard one section at a time.
I’ve read all the articles on this page and have come to the conclusion that you can’t kill Bermuda grass period. I have it all over my lawn and coming through the cracks everywhere. It’s coming out of the ground from under my Koi pond, though I had to admit it took about 20 years to do so. Now though it is staying with a vengeance. For my yard about 20+ years ago I dug a 2 foot deep swimming pool filled it with about 4″ of lye than filled it with a lot of sterilized soil, rolled it and laid sod. That lasted a good 10-15 years. But it is all back with a vengeance again. So just started to cultivate it as lawn and keep stimming it every week. I’m seriously thinking of about a 20-30% solution of sulphuric or hydrochloric acid. Maybe not. Thinking of selling and moving to where it does not grow. I don’t remember ever seeing it in Australia. Paspalem was the worst we had a sticky, tall, grass, weed, that stuck to your socks, shoes, pants, etc. That may be the best place to go for now. It’s ,moments like these you need Mintees.
Glad you enjoyed Richie!
Thanks for sharing your experience, and good luck! I think maybe of us would agree that the coronavirus has allowed for more time in the garden!