Controlling Monkey Grass: How to Stop Liriope From Spreading
If you find that lirope is taking over parts of your garden, these practical tips for controlling monkey grass will help.
Monkey grass (liriope) is often planted as a low-maintenance ground cover, but it can quickly become a problem when it spreads beyond the area where it was originally planted. Runners can creep into flower beds, lawns, and garden borders, making this perennial plant very difficult to contain.
All is not lost, though. There are several effective ways to keep monkey grass from growing out of control. Whether you want to slow its spread, create barriers, or remove it completely, the methods below will help you reclaim your garden space.
Before you start, it helps to know which type of liriope you have, since some varieties spread much more aggressively than others.
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Which type of liriope do you have?
There are two types of monkey grass – the clumping type (easier to control) and the spreading type (much more aggressive). Here is how to tell the difference in your yard.
Clumping liriope (Liriope muscari)
This type will spread but tends to stay more where you planted it.
- Forms clumps that spread slowly outward from the crown
- Tight clumps get wider over time, but don’t send out aggressive underground runners
- Has a compact root cluster that won’t overtake nearby plants too easily
- Great for lining sidewalks and as borders in garden beds
- Low maintenance. Requires little maintenance to keep it where you planted it
- The variegated version – Liriope muscari ‘variegata’ is the least invasive type.
Spreading liriope (Liriope spicata)
Creative Commons Attribution 3.0 Unported License. Photo Credit Wikimedia
This is the most aggressive type of monkey grass and the hardest to control.
- Aggressive rhizomatous spreader that can take over areas quickly
- Spreads rapidly in all directions via underground rhizomes
- Plants can pop up some distance away from the original clump
- The creeping nature can invade neighboring garden beds and lawns
- Perfect for large, bare areas to help control soil erosion
- High maintenance – needs edging, root barriers, or extensive manual digging to keep it under control
How to control monkey grass (liriope)
Given the right conditions, invasive monkey grass will grow aggressively and take over a border in 2-3 years. If left untended, monkey grass can be quite difficult to remove since its roots also form dense clumps. Here are some tips for controlling monkey grass.
Start early before it spreads
Once liriope establishes extensive runners or forms thick clumps, controlling it becomes significantly harder. The most effective time to manage monkey grass is when it first begins creeping beyond its intended area.
- Watch border edges early in spring to see how much area your monkey grass covers.
- Remove new shoots before they begin rooting deeply in the soil.
- Don’t allow monkey grass to form continuous mats in beds or turf areas.
- Continue monitoring its growth. Monkey grass continues to send out runners during the growing season.
Digging up edge growth (First-line control method)
This is your primary physical control method for small invasions of monkey grass. This method will keep monkey grass from growing into flower beds or encroaching into lawn areas.
- Use a sharp spade or garden knife.
- Cut straight down along the edge of the area where monkey grass is growing.
- Lift and remove newly formed clumps or connected sections of rhizomes.
- NOTE: You must remove all connected root sections. Partial removal of sections leaves pieces that will regrow.
How to contain monkey grass with barriers
Barriers are not used to remove liriope. They are used to keep monkey grass from expanding in the future. Some effective barriers are:
- Deep landscape edging (plastic or metal)
- Physical root barriers installed at least 6–10 inches deep
- Hardscape boundaries (concrete, pavers, sidewalks)
- Monkey grass can also be grown in pots. This keeps the roots contained.
Protip: Barriers only work if they are installed in front of the spread line, not after monkey grass has already passed it. It’s important to inspect the barriers periodically. Monkey grass is very aggressive and can find weak points if barriers are shallow or broken.
How to keep monkey grass from growing back
It is not enough to dig an edge or install a barrier against monkey grass in spring. Monkey grass continues growing for the entire growing season!
- Check perimeter lines 2–3 times during the growing season.
- Remove new shoots immediately as soon as you notice them.
- Re-cut edges each year to reinforce boundaries.
What to expect after removal (regrowth)
Even when you remove what appears to be the entire plant, regrowth is still possible. That is because monkey grass can regrow from:
- Small root fragments that are left in the soil
- Underground rhizomes that weren’t fully dug out
- Missed runners extending beyond the visible clump of monkey grass
- A “cleared” area may show new shoots within a few weeks
- Previously dense patches will show more regrowth than new clumps
Be ready to do follow-up pulling
Controlling monkey grass is not a one-and-done removal process. Most often, you’ll require at least one follow-up removal session.
- First pass: major clumps are removed
- 2–6 weeks later: new shoots appear from missed roots
- Second pass: smaller regrowth is easier to spot and remove
This second phase is normal, not failure. It’s simply a part of controlling monkey grass.
Soil disturbance can create new growth
After digging, the soil is often loosened, which can actually make it easier to see regrowth. However, it can also bring hidden rhizomes closer to the surface where they will quickly start growing. You may notice:
- scattered shoots instead of tight clumps
- thinner, weaker growth compared to the original plant
- regrowth emerging around the edges rather than the center
These are all signs you’re in the “cleanup phase”.
Timing matters
Monkey grass is a perennial, so regrowth patterns align with seasonal growth cycles. Common patterns:
- Faster regrowth in warm months (spring through late summer)
- Slower or dormant appearance in cooler months
- “Surprise” shoots often appear when temperatures rise again
This is why many gardeners think removal worked in winter, only to see it return in spring.
How to remove monkey grass completely (step-by-step)
If monkey grass continues spreading despite your efforts to control it, or if it has already invaded large areas, full removal may be necessary. Unfortunately, the best remedy involves real work – digging.
This requires patience, since the process may need to be repeated for several months to remove monkey grass completely.
Step 1: Identify the type
- Identify which type of liriope you have – Liriope muscari, or Liriope spicata.
Step 2: Cut the foliage to ground level
- Use trimmers, a mower, or shears to cut the plant down to ground level – this makes removal easier.
- Bag the foliage and discard it so as not to leave any pieces that might regrow.
Step 3: Dig beyond the clump
- Use a sharp spade to dig at least 6-8 inches beyond the edge of the visible clump.
- Dig at least 8-12 inches out for Liriope spicata.
Step 4: Lift the plants
- Remove entire clumps where possible.
- Shake the soil to expose hidden root connections.
- Break apart dense mats so you can see any missed sections.
If you leave interconnected rhizomes, regrowth is almost guaranteed.
Step 5: Remove runners (spicata only)
- Follow the underground runners outward from the main clump.
- Pull or dig them as far as they extend.
- Treat any “new shoots” as part of the same plant system.
Step 6: Inspect the soil (for persistent patches)
- Rake soil to expose fragments.
- Remove any white/cream rhizome pieces.
- Look for small crown sections that can re-root; even small pieces can regrow into new plants!
Step 7: Monitor any regrowth (important)
- Check the area every 2–3 weeks during the growing season.
- Pull new shoots while they are small and weak.
- Do not allow them to re-establish a root network.
- Add mulch – bare soil is easier for fragments to re-establish themselves.
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Is monkey grass taking over your garden? 🌿😬 Learn how to control or completely remove liriope before it spreads any further into your flower beds and borders. Practical tips that actually work 🧤✂️ #GardeningTips #WeedControl… Share on XPin these tips for controlling monkey grass
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Admin note: This article for controlling monkey grass first appeared on the blog in June 2017. This post has been updated with new photos, a printable project card, and a slideshow video about growing liriope.
How to Remove Monkey Grass Completely
Learn how to completely remove monkey grass (liriope), and stop it from returning to your flower beds, borders, and lawns using practical methods that work.
Materials
- Liriope plants in a garden
Tools
- Sharp shovel
- Shears, trimmer, or mower
Instructions
- Identify which type of liriope you have - Liriope muscari, or Liriope spicata.
- Use trimmers, a mower, or shears to cut the foliage of the plant down to ground level.
- Bag the foliage and discard it.
- Use a sharp spade to dig at least 6-8 inches beyond the edge of the visible clump (8-12 inches for Liriope spicata).
- Shake the soil and break it apart to expose hidden root connections.
- Follow the underground runners outward and pull or dig them up.
- Rake the soil and remove any white/cream rhizome pieces.
- Add mulch to the cleared area.
- Check the area every 2–3 weeks. Remove any new shoots.
- This process may need to be repeated as new growth emerges.
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a “neighbor” with an unkempt yard planted (threw) some that rooted and is now invading our lovely (kept) lawn. what can we do to stop it from ruining our landscaped lawn?
Hi Diae. The very best way to control liriope is to dig it out. The plant spreads from underground runners and even with digging you are likely to get some that still root. Carol
We have the same problem. I’ve been fighting it for five years. I’m losing the battle and am just about ready to move.
We bought a house that has it everywhere. And the worse part…it was planted in a bed of 2-3″ rocks!! I don’t know what to do. Leave it and fill in the spaces it hasn’t invaded yet so it looks like it was supposed to be there or just remove all of it.
Hi Amanda. If you leave any of it, it will spread to fill the entire bed. Liriope grows from underground runners. It’s often used as a ground cover for that reason, but it is not always desirable.
My lirope growing along walkway to driveway is constantly being invaded with grasses that are ugly and a real pain to dig out. I am ready to kill off the lirope and replace it with a prettier sedum. How do I kill the lirope. I have to admit I sprayed it with Roundup, which killed most of grasses but not the lirope!
Round up won’t do anything to liriope. The plant is tough and sends out underground runners. The only real solution is digging it up and even then, you’ll get some of it come back the next year and will need to dig again.
I have my work cut out for me on this plant. I had noticed some of my lilley’s in the flower garden were ,at one time at the edge of the garden, now quit a ways back in the garden. I went to inspect the situation and found that the monkey grass had grown 2 feet out. I then wondered what this plant was capable of. I was shocked when I read your page. It is going to take weeks to get the monkey grass cleared out as it is planted more then 200ft down the flower bed plus 2 other areas that are 20ft. I plan to dig it up and replace it with the variegated variety. I think your idea of planting it in container’s and sinking them side by side will be a better way for me to keep an eye on it. so I have a lot of work to do to get to a happier garden and a happier me. thank you.
I had pretty much the same situation and had to dig mine up too. I now use the variegated version without a problem. The plain stuff is tough!
hi! I am one that uses monkey grass alot….my problem is the “other grass” that grows up into the monkey grass…I was told by an elderly woman that the only way to keep monkey grass “clean” was to pull the “other ” grass by hand, hasn’t mankind made a spray that will kill the “other” grass and not kill the monkey grass?
Hi Tina. I rarely use sprays in my garden, so I am afraid I don’t know of one.
Yes, you need to oil mix with hi-yield grass killer
@tina boggan, I bought a house where the previous owner planted monkey grass in a huge bed in the front yard 40 years ago. It has spread under and through the brick walk way across the next flower bed and into the front driveway. Someone at a garden center that I purchase grass killer to kill it in the walkway. Didn’t touch the monkey grass at all. (I think it made it mad) My solution so far is to mow it into a lawn and slowly “shape” the garden beds to limit where it goes. It does make a lovely and slow growing lawn.
How do you smother monkey grass to death? I pulled the leaves off and put six layers of newspaper on the ground and then covered it with a layer of plastic. On top of that am placing ground cover to prevent grass from growing. On top of that am placing a couple of inches of mulch. Please tell me that will work.
@Margret Sheffield, you need to dig it all out and then fill up the area with granulated gravel and sand and then do the rest of the task you plan to do. Might as well use the glyphosate concentrated before doing all of that.
How do you smother monkey grass to death? I pulled the leaves off and put six layers of newspaper on the ground and then covered it with a layer of plastc. On top of that am placing a couple of inches of mulch. Please tell me that will work.
Monkey grass is one of the toughest plants that I have come across. The only way that I have found effective in really controlling it is to dig it up. Even then the roots may produce more that will need digging up.
@Margret Sheffield, It grew up through the weed barrier I had down all over my flower bed
Posts will control Bermuda grass in regular and variegated monkey grass. Image will control nut grass in it.
Can I keep monkey grass short? Mine is too tall for my liking. This would require trimming/cutting a few times per year. North Texas.
Hi Todd. if you cut it, the grass will bush out and still grow up, so it would require frequent trimming.
Your article has conflicting information in it. You say that monkey grass (Liriope) is not a grass, which is true, but then recommend grass killers such as Poast and Fusilade as chemicals that will control it, which is false. Chemicals in these products, sethoxydim and fluazifop-p-butyl respectively, are specific to grasses so they won’t harm monkey grass which isn’t a true grass. I would suggest removing that section of your article. Also, it is true Liriope has some tolerance to Roundup, or products containing glyphosate, but it can provide some control if applied properly at the right rate and with persistence; one application won’t get rid of it.
Thank you for the information David. I’ve removed the recommendations for the grass killers based on your info. I appreciate you taking the time to suggest it. I didn’t add the part about Round up since so many gardeners are against using it, but will leave this info in your comment. Carol
If I spray the shoots with round up, will it kill the whole plant or just the runners? I would like to keep the plant themselves.
It will likely damage the plant (and could kill it) but not the runners. The only way to stay in control of the runner, in my experience is to remove them as they grow. Liriope is very invasive.
What if I put large stones along the border of my monkey grass? Will that reduce spreading? I like the monkey grass, I just like it in a neat row!
Monkey grass will even grow underneath asphalt walkways. Large stones may keep them contained for a while but eventually they will find their way under them.
I have a HUGH long bed that is surrounded by loriope….it is a nightmare…which variegated loriope do you have that is just in a clump???
It is called liriope muscari variegata. I’ve written a post about it here.
@Carol Speake, thanks soooo much…!!!
Will boiling water slow it down?
Temporarily but it will also kill plants nearby.
Will Roundup kill monkey grass? I love monkey grass but it is getting in the way of my air conditioner drain outside so some of it needs removing. I am not able to dig it out due to my age.
Monkey grass grows from underground runners and is very hard to kill without digging the entire plant and roots up.
I really need some help, I have a lot of nice monkey grass I planted many years ago but wild African violets have invaded it. Now it looks awful with the violets mixed in. How can I kill the violets and not hurt the monkey grass? I know it will have to be a chemical spray of some kind but I don’t want to kill my monkey grass.
I don’t use chemicals much but the only thing I can think of is to “paint” the roundup directly on the wild violets. However, they grow from underground roots, so killing them will be very difficult.
I’ve been saving my paper coffee filters and use one at bottom of pot for drainage. It keeps the potting soil from leaking out but allows water to drain. I’m betting that if I line the hole for a monkey grass plant, it should slow down the spreading of new plants. Is that a logical assumption? My HOA neighborhood uses recycled water so I’m having to supplement the alkaline soil with acidifier and used coffee grounds. to correct the PH.
I”ve never tried this but I assume it would have some effect. Eventually, though the coffee filter would break down and the grass would still grow outside the hole.
@HEBer, it will grow through a weed barrier so my guess is a coffee filter won’t be any more effective.
I had to dig it all up. It was taking over my flowerbed. Thanks for the information. I also had weed barrier down and this stupid plant grew up through the barrier. Very strong willed plant.
I planted the invasive lirope by accident in my mulch bed, I have tried all summer long to try and kill it. I have put everything on it. Round up, poison ivy killer, diesel fuel, boiling water, vi e & brush killer, and nothing works. I have dug it all up, and sprayed the ground, covered it with a tarp. But it still comes back. I’m going to try again this fall and see of I can kill it over the winter when it’s ot growing so aggressively. If anyone has successfully killed lirope, please advise. Much thanks.
I managed to get mine all up with digging and then consistent pulling out of any stray pieces over about 2 years. It was in a row along border though, not filling a while bed. In the bed where it had bigger clumps, my husband dug it up. Digging really is the only way that works for me, and then redigging when some comes back. Covering the entire area with black plastic might kill it all, but it will kill everything else too.
@Carol Speake,
I have had it with the variegated liriope. It was planted in 5 beautiful clumps about 13 years ago. At that time, Thick fiber weed barrier was laid down then several inches of river rock, and then the plants were dug in. Now it is a major task just to get under all that to get to the roots. I think that the layers on top of the soil encourages the runners underneath. So I am removing everything. Then will work the soil to pull out as much as possible. The weed barrier is going in the garbage but I will return the rock to the bed. I will never plant monkey grass again.
I have pretty good luck with variegated liriope here in NC but the all green variety is a no no with me now.
Can you til it up or does it have be dug up with a shovel?
I wouldn’t till the soil around it. Monkey grass will leave tiny bits of roots if you do this and any of them could regrow. The only fool proof way that I know of is to dig the plants up completely. Poisons might do it, too, but I don’t use them.
I am looking for ways to kill Bermuda grass that is taking over my variegated lirope.
I don’t grow Bermuda grass so I don’t have first hand knowledge of how to control it. It spreads by underground runners, so if you have liriope in a border, putting below ground edging in place around the border may help.