How To Kill Monkey Grass.. or Just Keep it Under Control!

how to kill monkey grass

Many people grow monkey grass as an ornamental in their flower beds or as an effective edging plant. It’s super easy to grow but it can easily get out of control and invade your lawn. If this has happened, you’ll want to know how to kill the monkey grass to stop it taking over your precious lawn.

Killing monkey grass is not easy but we’ll look at some ways you can manage this with a little time and effort.

What Does Monkey Grass Look Like?

Another name for monkey grass is Liriope. There are 2 types of Liriope which are commonly grown by gardeners.

Liriope Muscari, commonly known as lilyturf, is a clumping form of monkey grass with grass like evergreen foliage and purple flowers. These flowers produce berries on a spike in the Fall. This variety of monkey grass makes an attractive edging plant and is unlikely to spread into your lawn.

The other variety of monkey grass, Liriope Spicata, is commonly known as creeping lilyturf. This is the variety that can be a problem for many gardeners. It spreads through an underground root system known as rhizomes. It has dark green, glossy leaves and white or lavender flowers.

Because of its aggressive spreading habit, Liriope Spicata can be quite difficult to remove once it’s invaded your lawn.

Be aware that mondo grass, Ophiopogon japonicus, is also often mistakenly called monkey grass.

How To Remove Monkey Grass From Your Lawn

There are a couple of ways that you can tackle the removal of monkey grass from your lawn.

1. Dig It Out

This method will take some time and vigilance on your part. Firstly, you’ll want to mow the monkey grass back to effectively damage the crowns. Then you have to dig it out making sure that you remove as many of the underground rhizomes as you can. Also take some of the surrounding soil as well.

You’ll then have to be vigilant and check the area every few days for any new growth. These new plants will also have to be dug up including all their rhizomes. You can also spray the roots with white vinegar. However, be very careful as the white vinegar will also kill any grass that it comes into contact with.

You may find that this method can take several months before you can totally eradicate the Liriope from your lawn. But if you’re vigilant and keep on top of it, you’ll eventually rid your lawn of this pesky weed.

2. Use A Herbicide

The only effective herbicide which will kill the Liriope is one containing glysophate like Round-up. I’m sure you’re aware though, that this herbicide will also kill your grass.

Therefore, if using this method, it’s best to apply the glysophate using a sponge or paint brush. Paint the herbicide directly onto the monkey grass, being careful not to drip any onto the surrounding grass.

Before applying the herbicide, cut back the Liriope. This will stress the plant enough to make the use of the glysophate more effective. Also, try to do this on a sunny day.

Once again, you’ll have to be vigilant when using this method and watch out for new growth. If you see new plants emerging, re-apply some more herbicide. Keep doing this until no more new growth emerges.

How To Keep Monkey Grass From Spreading

If you do like the look of Liriope and want to use it as an edging plant, you’ll want to stop it from spreading into your lawn. The best way to do this is with a physical barrier between the Liriope and your lawn.

This can be in the form of any type of edging that you can install and bury deep enough to stop the rhizomes from getting around it.  You’ll have to bury this edging at least 4 inches into the ground.

Another effective way to have a nice Liriope border is to keep the plants in their pots. Then bury the pots and cover the top with some mulch. The pots form a hard barrier to effectively stop the rhizomes from spreading.

If you do this, however, the plants will eventually become pot bound and you’ll have to take them out and divide the plants.

how to keep monkey grass from spreading

If All Else Fails, Call A Professional

If you’ve tried the above methods to rid your lawn of monkey grass and you still have some coming up, it might be time to call a professional gardening company or horticulturalist. Their time and expertise will help you get on top of the problem, once and for all.

Frequently Asked Questions:

Is monkey grass poisonous to dogs?

According to the U.S. Department of Agriculture, Liriope is a non-toxic plant. However, like all other plants, if consumed in large quantities, the berries can cause a little stomach upset.

What is monkey grass good for?

Liriope can be an excellent ground cover and edging plant especially in shady areas. It can also be used on slopes to help with any erosion problems. This is because the underground rhizomes will help to hold the soil together.

What is the difference between mondo grass and monkey grass?

Although mondo grass is sometimes mistakenly referred to as monkey grass, they are actually two different species both belonging to the lily family.  Mondo grass, Ophiopogon japonicus, has flowers which appear inside the foliage. On the other hand, monkey grass or Liriope has flowers which bloom on stems above the foliage.

Final Thoughts

If you have monkey grass growing in your lawn, you’re going to spend some time and effort to get rid of it. You can either dig it out by hand or use a herbicide containing glysophate.

Both methods will require you to be vigilant and remove or poison any new growth as soon as it appears. In fact, it may take several months to rid your lawn of monkey grass totally.

Therefore, if you’d rather spend your weekends doing more pleasurable things, you can always call in a professional to help you to get rid of this invasive plant in your lawn.

Leave a Comment

Your email address will not be published. Required fields are marked *