Zoysia grass is a popular warm-season turf in Texas, prized for its dense, carpet-like growth and ability to withstand the region’s high heat and drought conditions. Properly timed fertilization is a significant component of maintaining the turf’s desirable appearance and overall health. Because Zoysia is slower-growing than other Texas varieties, it requires a specific feeding schedule that supports growth without encouraging excessive thatch buildup. Understanding the exact “when” and “what” of fertilization is more effective than relying on a simple calendar date.
Timing the Initial Spring Application
The precise moment to apply the first spring fertilizer to Zoysia grass is determined by soil temperature, not the calendar date. Zoysia grass must have fully broken dormancy and be actively growing to utilize nutrients efficiently. This active growth phase begins once the soil temperature, measured four inches deep, consistently reaches 65 to 70 degrees Fahrenheit.
Fertilizing before the grass is fully awake risks wasting nutrients and feeding emerging weeds. A visual cue for readiness is the lawn reaching “full green-up,” meaning the turf has regained its color after the winter dormancy period. For North Texas, this often occurs around mid-April, while warmer South Texas regions may see this in early March. Applying a nitrogen-rich fertilizer too early can force the grass to grow before its root system is fully developed, potentially making it vulnerable to later summer stress.
Waiting for the consistent 65-degree soil temperature ensures that the grass’s roots are ready to take up the spring nutrient boost. This initial application helps the Zoysia recover from winter and promotes the dense, lateral growth that homeowners desire. It is a foundational feeding designed to set the stage for a healthy growing season.
Mid-Season Fertilization Strategy
After the initial spring application, the mid-season strategy involves a schedule of smaller, more frequent feedings throughout the peak Texas growing months. Zoysia grass is best maintained by “spoon-feeding” nutrients, meaning lower application rates spaced consistently apart. This approach helps sustain color and density without causing the rapid, excessive growth that leads to heavy thatch accumulation.
Subsequent applications should be spaced every six to eight weeks, continuing throughout the summer. This regular feeding pattern supports the turf through the intense Texas heat and heavy foot traffic. An established Zoysia lawn typically requires between one to two pounds of actual nitrogen per 1,000 square feet annually, which should be split across these multiple summer applications.
The timing of the final application is as significant as the first, as it prepares the grass for winter dormancy. Fertilization should stop in late summer or early fall, typically six to eight weeks before the first expected frost in your specific region. This cessation of nitrogen allows the grass to naturally slow its top growth and direct its remaining energy toward strengthening its root system and improving winter hardiness.
Choosing the Right Fertilizer Blend
Selecting the correct fertilizer blend is crucial for Zoysia health, particularly in the diverse soil conditions found across Texas. For general maintenance, Zoysia grass responds well to a complete turf fertilizer with a nitrogen-to-potassium ratio that is relatively balanced, such as a 3-1-2 or 4-1-2 N-P-K ratio. A blend like 16-4-8 or 15-0-15 is often recommended, with the emphasis being on nitrogen (N) for growth and potassium (K) for stress resistance.
The formulation of the nitrogen component is particularly important for Zoysia in the Texas heat. It is strongly recommended to use a blend that contains at least 50% slow-release nitrogen. Slow-release nitrogen provides a steady supply of nutrients over a period of six to eight weeks, which is necessary to prevent the sudden flush of growth and potential burning associated with fast-release products during high temperatures.
Texas soils, especially the alkaline clay varieties common in Central and North Texas, often bind with micronutrients, making them unavailable to the turf. Iron is a common deficiency, and its supplement is a valuable tool for maintaining a deep green color without over-applying nitrogen. Applying an iron supplement, often with an N-P-K ratio like 0-0-4 with high iron, can enhance the turf’s color without promoting excessive top growth. Before selecting any specific blend, a soil test should be performed, as it will provide a precise map of existing nutrient levels and pH, allowing for the most effective and efficient fertilization plan.