Zoysia Lawn Care: How to Keep Your Zoysia Grass Healthy, Green, and Patch Free
There’s nothing quite as satisfying as a beautiful green lawn. It’s perfect for the kids to play on while the dog snoozes and the neighbors look on in envy.
Alright, maybe your lawn concerns aren’t so tied up in keeping up with the Joneses, but you would still like to have a nice lawn.
And if you’ve invested in Zoysia grass, you’ve chosen a lovely grass for the job. The trick is to keep your Zoysia grass happy, healthy, and ready to impress.
For that, you have to know how to take care of it. Problem is, most homeowners don’t have a clue. That’s where we come in.
Keep reading for a comprehensive guide on how to keep your Zoysia healthy the whole year round and how to spot-treat problems if they arise. Even if you don’t know the difference between a dead patch and a fungal infection, you’ll be well-equipped to play lawn doctor.
What You Need to Know About Zoysia Grass
Zoysia grass is native to Asia and Australia, but it’s been in the United States since at least 1895, when Americans first became invested in their lawns.
As you can probably guess from its native habitat, Zoysia is a warm-season grass, which means that it grows during warm months and lies dormant during cold months. It’s also a perennial, which means it comes back every year (great news for your lawn!)
There are three main Zoysia species seen in the United States:
- Zoysia japonica
- Zoysia matrella
- Zoysia tenuifolia
They can be distinguished from each other by appearance, aggressiveness, and growth.
Zoysia japonica is the only Zoysia species with seed that’s available commercially (in the U.S., anyway). It has a light green color and coarse leaves.
Zoysia matrella is often called Manilagrass (it was introduced to the U.S. from Manila). It has a finer leaf than Zoysia japonica, but it’s also less cold-tolerant and grows slower.
Finally, Zoysia tenuifolia is unique because it tends to form small clumps, which makes it appear puffy. It’s even less cold-tolerant than Zoysia matrella, so if you live somewhere with four seasons, this may not be the ideal grass for you.
Characteristics
Regardless of the type of Zoysia, most species have a few traits in common.
In general, Zoysia sod provides a thick, carpet-like cover for your lawn. In fact, the carpet of Zoysia is so thick that weeds have trouble breaking through it.
It performs well in drought conditions, is highly adaptable to different types of soil, and is even salt-tolerant. This is because Zoysia has a deep root structure which allows it to reach deeper underground to extract moisture.
That said, Zoysia doesn’t recover well from two things: cold and constant traffic.
As we said, Zoysia is a tropical grass by nature, so it likes climates that resemble its original home (climates similar to Japan and other southeast Asian countries). In the U.S., that usually means southern California and the Deep South.
And if you have a soccer-playing family or a dog that likes to run in circles in the yard, Zoysia may not be the best option, as it doesn’t always recover well from frequent foot traffic in the same areas.
Since Zoysia is a warm-season grass, you’ll see the best results when you plant the sod in periods when the grass is actively growing (late spring through late summer).
How to Care for Zoysia Grass
Now that you know a bit about the grass that makes your lawn beautiful, we can talk about how to take care of it.
Spring
Spring is the busy season for Zoysia. Your lawn is just starting to wake up from the winter, so it’s going to need some extra TLC to thrive in the warm months.
To that end, let’s start with the basic lawn care task: mowing.
Since it isn’t summer, you’re going to want to cut your grass a bit shorter than you would in the summer. Think of it as the spring cleaning buzzcut. It will help encourage the lawn to grow back strong going into the summer. Just be careful not to set the mower too low–otherwise, you’ll scalp the lawn.
If you cut the lawn around 1.5 to 2 inches in the summer, reduce that by about half an inch in the spring to 1 or 1.5 inches. This is especially important if you already have an established Zoysia.
After the initial buzzcut, you can cut your Zoysia at its normal height.
One thing you shouldn’t do is over water. When allowing for rainfall, Zoysia needs about one inch of water per week. Mix it in with herbicide and pre-emptive fungal treatments.
Summer
Summer is when things really kick into gear.
Zoysia is growing full speed ahead during this time of year, so make sure you give it all the tools it needs to grow up healthy. That means regular mowing every three to five days or so.
When you mow, be careful not to remove more than ⅓ of the grass blade. Anything more than this will stress the grass and cause it to die out (or leave it vulnerable to other issues). When in doubt, leave it another day or two. As long as your lawn doesn’t look like an abandoned car lot, your neighbors will forgive you for it.
Now, watering. Three words. Do. Not. Overwater.
Just because Zoysia is tropical doesn’t mean it likes to swim. In fact, excessive watering leaves it vulnerable to fungal infections. It needs about an inch of water per week in the early morning, preferably all at once for a longer period of time.
It might sound fussy, but if you live somewhere with summer sun, the time of day does make a difference. If you water your lawn in the afternoon, it can burn in the sun. If you can’t do early morning, early evening works too.
Fall
Fall is when your Zoysia starts to slow down for the year, so now is the time to do preventative maintenance.
For example, application of fungicide will help your grass stay strong going into the cold months and keep any lingering fungi from holding on into the new year.
Since your Zoysia isn’t growing as fast, you don’t need to worry about mowing as often either. Letting it grow taller helps encourage a deeper root structure to support the stalk, which will help it stay healthy and hearty in the winter.
You don’t need to worry about watering as often either–excessive watering leaves your grass vulnerable to root rot and other diseases.
Care Tasks
That’s your overall seasonal maintenance. However, there are several care tasks that are worth examining in closer detail.
After all, if you want a beautiful lawn, you have to know how to take care of it.
Mowing
First is the task you’re already familiar with: mowing.
We said before that you should mow the lawn shorter at the start of spring and progressively longer until you hit winter. But the blades you use to cut your grass are also important.
You see, if your mower blades are dull, you don’t actually cut the grass leaves. You tear them. It might seem strange to think of your grass as something that can get injured, but that’s exactly what happens. And if your grass is torn, it’s more susceptible to disease, much like a cut at risk of infection.
Think of it like trying to shave with a dull razor. It’s painful, frustrating, doesn’t actually work, and leaves you more at risk of minor infections every time you touch your face.
In general, you should sharpen the blades after every 15,000 square feet of lawn mowed, or if you see ragged edges when you cut the lawn.
Aeration
If you want your grass to breathe, you need to aerate.
Aeration is the process of punching holes into the turf and sod to alleviate compaction. This allows the root system of the Zoysia to get oxygen and helps correct drainage problems.
Much like human breathing, it’s essential to healthy grass.
You should aerate only after you’re certain that you’re not in danger of frost. Otherwise, the frost can penetrate the root system and seriously damage your lawn.
However, if you applied pre-emergent herbicide anywhere from late February to mid-March, hold off on aeration until just before your next herbicide application. The Zoysia can tolerate herbicide on the leaves, but you don’t want it to seep too far into the root system, as this prevents Zoysia seeds from germinating.
There are also new liquid aeration options available now that are much less labor intensive and don’t have the risk of damaging sprinkler heads, valve box lids etc. Call Abracadabra Pest & Weed to inquire about this service.
Fertilization
If you want to play it safe with fertilizer, you can start by testing your soil.
You don’t necessarily need to test the soil if you’re confident in your grass. The biggest benefit here is that it will help spot any nutrient deficiencies you should try to make up. This table can give you an idea of how to fertilize your Zoysia.
But if you’re not interested in the fuss, you don’t need to test the soil first.
Whatever you do, don’t fertilize your soil if you’re still at risk of frost. If you’re 100% committed to spring, you’re clear to forge ahead.
Weed Control
Next comes your least favorite part of lawn care: weed control.
There are plenty of common garden weeds out there, all of them hardy and notoriously persistent. Nothing ruins the appearance of your lawn as much as a patch of weeds.
However, you don’t want to kill your grass in the process of killing your weeds.
The best way to protect your grass is to be prepared. Apply a pre-emergent herbicide early in the year to prevent roots from taking hold (check your climate area for the best times of year to do this). After the initial application, wait eight to ten weeks and apply it again (but aerate your soil first if you haven’t gotten around to it).
If a few weeds do survive your herbicides, turn to post-emergent herbicide.
In the meantime, you can keep your weeds in check by mowing and bagging them along with your grass clippings.
Insect Management
Whether you’ve got grubs, chinch bugs, ants, or cicadas, you’ll have to keep the critters in check if you want your grass to flourish.
The good news is that winter weather conditions usually keep insects at bay. That gives you time to prepare in the spring.
As temperatures start to warm, keep an eye out for any signs of insect damage, especially mole crickets. Unless the damage is heavy, you shouldn’t apply insecticide until after the grass has greened.
You should also be on the lookout for grubs (the white larvae of beetles). To do this, cut a square-foot piece of sod and peel it back. If you see more than six grubs, get an insecticide labeled for grub management and apply as directed. You don’t want these things to grow into mature beetles and hatch more grubs.
Spot Treatment
Let’s say you did everything right in tending to your lawn. And yet, despite your best efforts, your lawn is still having difficulties.
Like, for example, a spreading brown patch that has nothing to do with your dog’s favorite toilet location.
The bad news is that sometimes, much like a person, your grass gets sick. When that happens, it needs you to step up and take care of it. It’s not just for aesthetics–you don’t want the problem to affect other plants.
So if your grass shows signs of illness, the first step is recognizing what’s wrong. Here’s what you need to know.
What is Brown Patch Disease?
Also called large-patch disease, brown patch disease is a fungal infection caused by the Rhizoctonia species of fungus. It’s the most prevalent Zoysia grass disease out there.
You may be familiar with it already, based on its signature sign.
Symptoms
As the name implies, the most obvious sign of brown patch disease is, well, a brown patch of grass.
The disease typically causes thinned, circular patches of brown grass. These patches can range from a few inches to a few feet in diameter. That said, if conditions are favorable (i.e. warm and humid) the fungus may kill a large portion of the lawn without any obvious circular pattern.
The easiest way to diagnose brown patch disease is to check the shoots. Diseased shoots are easy to pull out of the ground and are browned at the sheath.
Treatment
Brown patch disease is most often caused by:
- Over-fertilization in the fall
- Poor drainage
- Excessive irrigation
- Excess thatch
- Low mowing height
So the first thing you need to do to correct the problem is to figure out what you did to leave your Zoysia susceptible. That way, you won’t weaken your grass again.
It’s difficult to eliminate brown patch spores completely, but you can strengthen the Zoysia enough to prevent the spores from seriously damaging the grass in the future.
You’re going to need fungicides to help cure the fungus, but you also need to eliminate growth conditions. One of the big things that attracts fungus is excessive nitrogen content, which clumped Zoysia tends to promote. Treatments to balance your soil’s pH can usually fix this problem.
You also want to prevent any excess moisture. Fungus thrives on moisture, so make sure to only water your lawn when needed and only to a depth of four to six inches.
What is Take All Patch?
Then, there’s take all patch. Take all patch is a serious root disease created by a soil-borne fungus. If left uncontrolled, this disease can destroy large sections of your lawn.
Symptoms
You’ll first notice this disease because it yellows out your grass in circular areas or in random patches. It’s often misdiagnosed as brown patch disease for this reason.
But if you take a look at the roots, you’ll get a clear diagnosis.
Take all patch causes the roots to rot, which makes it easy for you to pull grass out of the ground (the root system is weakened). The key difference lies in the stolon.
In brown patch disease, the roots are slimy and rotten but the stolon remains green, allowing your grass to recover later in the season. Take all patch, as the name implies, takes no prisoners. It causes the root system to rot, much like brown patch, but it goes one step further and kills the stolon gradually, wiping out your grass.
Treatment
If your grass has take all patch disease, it’s time to reevaluate your care practices.
First, your watering practices. Many people water their grass shallowly and frequently, but Zoysia does best when watered deeply and infrequently. This also prevents moisture buildup over time, which is what leaves the grass vulnerable to fungi.
You should also use fungicide at the first sign of take all patch. Make sure to remove diseased grass clippings when you cut the grass, as this will prevent the fungus from spreading.
If you’ve had take all patch in the past, you also need to take preventative measures to ensure that the fungus doesn’t come back next spring. Much like your grass, fungal spores can lay dormant when conditions are too cold for them–and come back with a vengeance in the spring.
Leaf Spot
Another common lawn disease is leaf spot or melting out, which is the name given to a broad family of fungal diseases affecting grass.
Symptoms
Much like brown patch disease, the name tells you what to watch out for.
The most obvious sign of leaf spot is, well, spots on your leaves of grass. Individual blades will have a large number of lesions that look like cigarette burns. The grass will begin to turn brown, making it look dried out or underfed and concealing the actual issue.
The leaf spots themselves are unsightly, but they don’t do a great deal of damage to the grass. The troublesome part is the melting out phase.
Melting out happens during hot, dry weather and causes large patches of grass to dry out. Aside from leaf spots, though, it’s difficult to spot the difference between melting out, underfed grass, dried out grass, or some other fungal disease.
Treatment
So the best thing you can do to protect your grass from leaf spot is to prevent leaf spot from forming.
As with other fungal infections, leaf spot thrives under wet conditions, especially if you over-water your grass.
So, in case it hasn’t sunk in yet: water your grass shallowly and infrequently. Anything further can encourage fungal growth and one pathetic lawn.
Regular fertilization and aeration goes a long way toward disease prevention, as does regular application of fungicides. Just be careful not to over-fertilize, as this can weaken your Zoysia and leave it vulnerable.
Caring for Your Lawn the Right Way
Your Zoysia grass plays such a big role in the appearance of your home, why wouldn’t you want to take care of it? It’s a reflection of a homeowner who cares about their house and wants to make it look amazing.
Of course, if you work a busy job or have a perennial black thumb, it’s hard to dedicate yourself to full-blown lawn care. That’s where a lawn service can help.
Good news: you’ve found the perfect lawn service for the job.
We help with everything from lawn fertilization to disease control. That way, you can rest assured that your lawn is in good hands and get back to what matters most: your loved ones.
If you’d like to book our services, check out our service area and use our contact page to get in touch.