When To Fertilize Zoysia Grass

Knowing when to fertilize zoysia grass is the key to a thick, green, and resilient lawn. This essential seasonal feeding guide will walk you through the simple timing and steps to keep your turf looking its best.

Zoysia is a tough, warm-season grass known for its drought tolerance and dense growth. But even this hardy grass needs the right nutrients at the right time. Feeding it properly prevents weeds, encourages deep roots, and helps it survive stressful conditions. Let’s break down the yearly schedule.

Your fertilization schedule revolves around one main rule: feed during active growth. Zoysia grass wakes up in late spring, grows strongly in summer, and goes dormant after the first hard frost in fall. You should only fertilize within this window of green growth.

The Best Times of Year to Feed Your Lawn

The general zoysia fertilization calendar includes two to four applications. The exact number depends on your soil health and desired maintenance level. Here’s the standard framework:

Late Spring (Greening-Up): Apply your first fertilizer when the grass is fully green, not just when it starts to wake up. This is usually when soil temperatures consistently hit 70°F. Early feeding can encourage weeds.
Early Summer: A second application about 6-8 weeks after the spring feeding supports strong growth for the hot months ahead.
Mid-Summer (Optional): Only if needed. If your lawn looks pale or growth slows, a light feeding can help. In rich soils, you might skip this one.
Early Fall: This is a critical feeding. A fall fertilizer helps the grass store energy for winter and promotes a quicker green-up next spring. Apply at least 6 weeks before your expected first frost.

Never fertilize zoysia in winter when it’s dormant. The grass can’t use the nutrients, and they’ll likely run off or feed winter weeds.

Choosing the Right Fertilizer for Zoysia

Not all lawn fertilizers are created equal. You need to look at the three numbers on the bag, which represent Nitrogen (N), Phosphorus (P), and Potassium (K).

Nitrogen (N): This is the most important for leaf and blade growth, giving that lush green color. Zoysia typically needs 2-4 pounds of actual nitrogen per 1000 sq. ft. per year.
Phosphorus (P): Supports root development. It’s often limited by law in many areas because excess can pollute waterways. A soil test will tell you if you need it.
Potassium (K): Promoves overall plant health, stress tolerance, and disease resistance. Crucial for surviving cold winters and summer heat.

A common and good choice for zoysia is a slow-release nitrogen fertilizer with a ratio like 15-0-15 or 16-4-8. Slow-release feeds the grass gradually over time, preventing a surge of weak growth and reducing burn risk.

Step 1: Conduct a Soil Test

This is the most overlooked step. A soil test tells you exactly what your lawn lacks. You can get a kit from your local county extension office. It will give you precise recommendations for nitrogen, phosphorus, potassium, and lime. Don’t guess—test!

Step 2: Calculate How Much Product You Need

Once you have your ideal N-P-K ratio, you must calculate how many bags to buy. Use the nitrogen number to figure it out.

Find the percentage of nitrogen in your fertilizer (the first number).
Divide 100 by that percentage. This gives you the pounds of fertilizer needed to get 1 lb of nitrogen.
Multiply that by your target pounds of nitrogen per 1000 sq. ft.
Multiply that result by your lawn’s area in thousands of square feet.

For example, for 2 lbs of N with a 15-0-15 fertilizer on a 5000 sq. ft. lawn: 100/15 = 6.67. 6.67 x 2 lbs N = 13.34 lbs per 1000 sq. ft. For 5000 sq. ft. (5 units), 13.34 x 5 = 66.7 lbs of fertilizer total.

Step 3: Apply Fertilizer Correctly

Proper application ensures even coverage and prevents damage. Follow these steps:

Mow your lawn a day or two before applying.
Use a calibrated broadcast spreader for best results.
Fill the spreader on a hard surface, not on the grass, to avoid spills.
Apply half the product walking north-south, and the other half walking east-west. This criss-cross pattern prevents streaks and missed spots.
Lightly water the lawn after application to wash the granules off the grass blades and into the soil.

Season-by-Season Care Tips

Fertilizer is just one part of the puzzle. Here’s how other care tasks align with your feeding schedule.

Spring Care

Wait for full green-up before any action. If you have a thatch layer over ½ inch thick, dethatch. Aerate if the soil is compacted. Apply pre-emergent herbicide for weeds if needed, but check compatibility with your fertilization timing. Your first fertilizer application comes after these tasks.

Summer Care

Zoysia thrives in heat. Water deeply but infrequently, about 1 inch per week including rainfall. Mow at the recommended height for your variety, usually between 1.5 to 2.5 inches. Never cut more than one-third of the blade at once. This is when you’ll do your mid-season feeding.

Fall and Winter Prep

The early fall fertilizer is your last major task. Continue to mow as long as the grass is growing. As temperatures drop, zoysia will begin to turn its characteristic brown dormancy. This is normal. Avoid heavy traffic on dormant grass. Do not fertilize in the winter.

Common Mistakes to Avoid

Fertilizing Too Early in Spring: This feeds winter weeds and can cause the zoysia to break dormancy too early, risking frost damage.
Using Weed-and-Feed Inappropriately: These products often don’t align with zoysia’s needs or the correct timing for pre-emergent weed control.
Over-Fertilizing: More is not better. Excess nitrogen leads to thatch buildup, increased mowing, disease susceptibility, and pollution.
Ignoring Soil pH: Zoysia prefers a slightly acidic soil pH of 6.0 to 6.5. If your pH is off, nutrients get locked in the soil. Lime or sulfur applications, based on a soil test, can correct this.

FAQ: Your Zoysia Fertilization Questions Answered

Can I fertilize zoysia grass in the fall?

Yes, early fall is one of the best times to fertilize. It strengthens the roots and improves winter hardiness. Just make sure to apply at least 6 weeks before the first expected frost.

What is the best fertilizer schedule for zoysia?

A simple and effective schedule is three applications: one in late spring after green-up, one in early summer, and a final one in early fall. Adjust based on your soil test results.

How often should you feed zoysia lawns?

Most lawns do well with 2 to 4 feedings per year. Heavily sandy soils may need more frequent, lighter applications because nutrients leach out faster.

Is it okay to fertilize zoysia in summer?

A light mid-summer application is fine if the lawn shows signs of nutrient deficiency, like yellowing. However, during extreme heat or drought, it’s better to hold off and just water properly.

Should I water after fertilizing zoysia?

Yes, a light watering is recommended. It helps move the fertilizer granules into the soil where they can start to break down and prevents them from sitting on the grass blades, which could cause burn.

Following this essential seasonal feeding guide takes the guesswork out of caring for your lawn. By understanding when to fertilize zoysia grass, choosing the right products, and avoiding common pitfalls, you’ll support a healthy, beautiful turf that can withstand the seasons. Remember, patience in spring and a timely fall feeding are your most important strategies. With consistent care, your zoysia lawn will be the envy of the neighborhood for years to come.