Why is My Zoysia Grass Not Growing?

Many grass varieties stay lush and green through various seasons and become dormant when the temperatures drop. Zoysia grass is a warm-season variety well-adapted to the warm and sunny Florida climate. While it usually enters dormancy in winter, it should return to its vigorous state when spring arrives.

However, if your lawn has turned completely brown, has brown patches, or is thinning out in some areas, you may have encountered a few problems with Zoysia grass. Resist the urge to spray for a disease as many homeowners would—many factors can result in these common Zoysia grass issues.

Most Common Zoysia Grass Problems & How to Address Them

Pests

Zoysia grass is generally grown from grass plugs or sod, characterized by its light to emerald green color, narrow blades, and low-maintenance properties. Although it has excellent tolerance to drought and foot traffic, it's not immune to pests, and among the most damaging are chinch bugs, grubworms, hunting billbugs, fall armyworms, sod webworms, and mole crickets.

Although small, chinch bugs pose a significant threat by extracting leaf juices and releasing toxins that dry out grass blades. They are most active in summer, with symptoms often resembling drought damage—large brown patches in your lawn. You can check for chinch bugs by checking the area between yellow-brown and healthy green grass. In their early stages, they appear orange to light red with a white stripe on their abdomen, transforming into black with white markings on their back as they mature.

Fungal Diseases

Zoysia grass generally exhibits greater resilience against diseases than other warm-season grasses. However, certain conditions, such as excessive thatch buildup, overuse of nitrogen fertilizer, and high humidity levels, can create a conducive environment for fungal diseases like brown patch fungus.

It appears as small circular patches of brown grass, sometimes turning into a vivid orange hue and reaching up to six feet in diameter when left unchecked. This disease tends to affect newly established lawns more severely than established ones. While it is more prevalent in spring, it can also affect grass during fall, when growth slows due to cooler temperatures or following floods or extended periods of heavy rain.

Heat and Drought Stress

Despite its inherent heat and drought tolerance, these environmental stressors can significantly affect your Zoysia grass. It may enter a dormant state or, in severe cases, risk dying off when exposed to extreme heat or prolonged drought conditions.

It requires approximately ½ inch of water weekly to keep your lawn healthy and green and about ¼ inch per week when dormant.

Is It Dormant or Dead Grass?

With the mild winter in Florida, grass doesn't ever stop growing in the region. But they grow significantly slower when the temperature drops to 50°F, which is usually experienced in January. Nevertheless, it remains possible for the zoysia grass to turn brown and not restore its green hue until spring.

Examining your grass closely determines whether it is dead or dormant. Dormant grass should be firm at the base and resist a gentle tug. Meanwhile, dead grass will be shriveled with dead roots and can be uprooted easily.

READ: What is the Best Fertilizer for Zoysia Grass Plugs

How to Maintain a Healthy Zoysia Grass Lawn

In some cases, the poor growth and susceptibility to common diseases in your Zoysia grass lawn is also a result of poor maintenance practices.

Using too much fertilizer, poor watering practices, and neglecting key aspects of lawn care can contribute to issues such as weed infestation, root rot, excessive thatch buildup, pest infestation, fungal infection, and an overall unhealthy lawn.

It's crucial to address these issues first before resorting to any treatments. Remove thatch regularly to promote air circulation, particularly in early spring when the grass emerges from dormancy. Address weed problems, ensure optimal moisture levels, and fertilize based on your soil's specific needs to support grass growth and ensure a healthy, thriving lawn.

Finally, for areas experiencing significant damage, repairing with Zoysia grass plugs emerges as a practical solution to replace dead grass and fill in sparse areas in your landscape.