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While neat lines of clustered grass make for very beautiful borders along lawns and gardens, it’s not quite as aesthetic when small clumps start sprouting on the smooth planes of your lawn.
Aside from being unappealing, these clumps also present a slight health hazard. If you have children that take to the lawns to run with abandon, they are simply one trip away from an injury.
The most common species of clumped grass found in the United States are either mondo grass (Ophiopogon japonicus) or monkey grass (Liriope muscari).
Both are highly similar in how they clump and are often considered interchangeable terms. However, monkey grass is definitely a hardier plant and is thus far more difficult to get rid of than the former.
Nonetheless, if you find your lawn riddled with clumps of monkey grass, take a moment before you call in a professional.
You might just be able to rid yourself of this problem with what you have at home. Read on to learn some DIY tips and tricks on how to kill monkey grass.
Why Do You Need to Kill Monkey Grass?
Before you learn more about how to kill monkey grass, you need to understand why doing so is necessary.
If you’re still new to the gardening scene, this might seem like a bit much over some clumps of grass in your lawn.
But killing stray monkey grass is actually a very important aspect of lawn maintenance.
The family of clumped grass forms is for the most part fairly harmless.
If it does spread onto your lawn, it’s typically more of an aesthetic issue than anything else.
There are some species like Liriope spicata that are more predatory and can suffocate the other flora in your garden, but that is not where the true issue lies with monkey grass.
The plant’s hardiness, which makes it such a gardening favorite for people who can’t devote as much time and effort to their lawns, unfortunately also means that it is very difficult to control.
Monkey grass grows very fast and is able to spread its seeds as far as 15 inches from where it’s rooted.
If left alone, it can also grow as high as three feet.
Thus, if you find yourself too lazy to de-weed some clumps, you might very well be signing up to de-weed your entire lawn in a matter of months.
How to Kill Monkey Grass
You might think you’re ready to get to the juicy bits of killing your monkey grass, but there’s some prep work you need to do with your lawn before that.
Mow your lawn such that the grass is an inch above the soil and only the plant crown is damaged.
This makes for easier de-rooting and also gives you better access for herbicide applications.
Another thing to keep in mind when deciding upon when to de-weed your lawn is how recently it’s rained in the past couple of days.
If there has been any form of heavy hydration on your lawns over the past two days, then wait a day or two more.
Wet, mulchy soil makes for extremely messy and difficult gardening.
Now that you’re a bit more ready to face your clumped foes, try these four tips to learn more about how to kill monkey grass:
1. Dig Out the Roots
This is by far the easiest means to rid your lawn of monkey grass.
This is also often a precursor to many of the other tricks to kill monkey grass, as it provides a solution at the root level.
Simply dig up the grass and try to remove as many plants by the root as you can.
Make sure you don’t pile the uprooted plants somewhere else on the lawn. All you’d be doing then is giving them fresh soil to spread their seeds onto.
Keep a wheelbarrow or a tarp sheet nearby to dispose of your roots. This will keep contact with other parts of your lawn to a minimum.
Keep an eye on these uprooted patches for a couple of days to see if there is any more growth.
If you do see any new shoots, you’ve most likely left behind a couple of roots and need to dig them up again.
If you want a bit more of a final solution, you can use white vinegar on the soil as well.
It acts as a natural herbicide and keeps any remnant roots from regrowing.
However, make sure you don’t get it on any of the neighboring plants when spraying.
White vinegar is extremely dehydrating to plant cells and essentially dissolves their membranes — there’s no saving your plant after that.
2. Boil Your Problems Away
Another highly effective way of killing stray monkey grass is to quite literally cook it.
Pouring boiling water over the unwanted grass causes a series of chemical changes in the plant that prevent it from growing and encourage wilting.
Once the plant is fully wilted, removing it becomes significantly easier.
This is also extremely good from an environmental standpoint and hot water doesn’t possess any of the damaging side effects on soil pH and density that herbicides do.
Simply dig up near the roots of the monkey grass clumps and use a funnel to pour the boiling water into the problem areas.
The usage of a funnel isn’t necessary, but if you’re blessed with shaky hands some extra guidance couldn’t hurt.
Let the water get absorbed into the roots of the plants and slowly let the plant wilt.
If it’s taking too long, you can also speed the process up by dripping some of the boiling water directly on the plant as well.
3. Stifle the Spread
If the clumping is too much for you to remove in one go, do some damage control — keep the clumps from spreading.
Set up root barriers that go at least 15-18 inches into the ground to prevent a spread at the root level.
Then, cover the confined area with a tarp or landscape fabric.
What this essentially does is lock your monkey grass in a room of sorts and suffocate it so it will stop spreading.
Bamboo root barriers that also come with heavy plastic sheeting work particularly well in this scenario.
Covering it with a tarp or landscape fabric will not immediately result in the plant dying. However, it will weaken it over the duration of two to three days.
This should make digging the roots up an easier task.
While you can do this at any time of the year, you will get the best results around summer.
The soil is already dry which means the roots don’t have a strong hold to start with. This makes them easier to weaken or wilt.
Another very neat trick is to plant vines along where the monkey grassroots have been dug.
Thus, any remnant monkey grass roots die from lack of nutrition and can be uprooted with the vines after one or two seasons.
4. Chemical Herbicides as the Last Measure
Your monkey grass problem may be a bit too severe to be undone with some homely measures.
You might have no other option than to turn to chemical herbicides.
This is a fairly drastic measure as it will have some side effects on your soil’s pH and can affect how the other plants in your garden or lawn will grow.
This is, of course, aside from the potential hazard to your lawn’s ecosystem that comes from the usage of chemical herbicides.
The most commonly used herbicide for these kinds of purposes is Round-Up, but any product with glyphosate as an active ingredient should suffice.
Glyphosate is a non-selective herbicide, which means it kills any plant it comes in contact with.
It is thus extremely important that you make sure you apply only at the roots of the problem areas and nowhere else.
You can alternatively find selective herbicides, that target only certain types of weeds. They shouldn’t impact the rest of your lawn. Be sure your herbicide targets the correct weeds.
Because monkey grass in general is such a survival-oriented species, one round of application will most likely be insufficient.
Try at least a few rounds of application to gain the best results.
What Can You Replace Monkey Grass With?
On account of its low-maintenance nature, monkey grass is a crowd favorite for lawns. However, there are several alternative species of clumping grass that can be just as easy to manage.
The first, of course, is the commonly known mondo grass. It is overall similar enough to monkey grass for the two to be mistaken for each other.
However, it does grow better in slightly milder, shadier environments.
It’s a denser clump which makes it better for areas with erosion and also grows shorter than regular monkey grass by a slight margin.
Another excellent alternative is lilyturf (Liriope spicata) which, frankly, has even better survival rates than regular monkey grass.
Lilyturf is a lot shorter and has a more uniform growth mechanism than clumping.
This makes it better suited as an alternative for monkey grass used directly as turf than as a lawn border.
Lilyturf is also fairly predatory in nature and can fill empty spots fairly quickly.
So, if you have other ornamental plants you maintain along with your lawn, it is definitely possible that you’ll catch lily turf encroaching their territories.
Takeaway – Keep Your Lawns Clump-Free
And there it is! Follow the above four tips on how to kill monkey grass closely to make sure your lawns are the smooth evergreen planes they were meant to be.
Let this be the last morning stroll you’ve had ruined because of a stubborn clump of monkey grass.