St. Augustine grass is a popular warm-season turf known for its lush, carpet-like appearance in many southern landscapes. Understanding its height characteristics is fundamental for cultivating a healthy and aesthetically pleasing lawn. Proper management of its vertical growth contributes significantly to the overall vigor and resilience of the turf.
Understanding St. Augustine Grass Height
If left unmowed, St. Augustine grass can reach heights of up to 12 inches, producing flowers and seeds. In lawn care, the focus is on the ideal mowing height for its leaf blades. This grass spreads through above-ground runners called stolons, which do not tolerate being cut by a mower blade.
The vertical growth of the grass blades, not the sprawling stolons, determines the appropriate mowing height. Maintaining the correct height protects these vital stolons, essential for the plant’s health and spread. Experts recommend a mowing height between 2.5 and 4.5 inches for St. Augustine grass to promote overall turf health.
The Importance of Ideal Mowing Height
Maintaining the recommended mowing height for St. Augustine grass is crucial for the lawn’s health and appearance. Proper height promotes deeper root growth, enhancing the grass’s ability to absorb water and nutrients. This contributes to improved drought tolerance and greater capacity to withstand environmental stresses like heat and disease. A dense, properly mowed lawn also suppresses weed growth by shading the soil.
Mowing St. Augustine grass too low, or scalping, can severely stress the turf. Cutting into the stolons can damage the grass, leading to thinning, discoloration, and increased susceptibility to pests and diseases. If the grass grows too tall, it can lead to thatch buildup, which harbors pests and diseases. Taller grass can also droop, preventing a clean cut and impacting photosynthesis.
Mowing Best Practices for St. Augustine Grass
To maintain the ideal height for St. Augustine grass, follow consistent mowing practices. The “one-third rule” states that no more than one-third of the grass blade’s height should be removed in a single session. For example, if aiming for a 3-inch lawn, mow when the grass reaches 4 to 4.5 inches. This minimizes stress and allows for sufficient leaf surface area for photosynthesis.
Mowing frequency depends on the grass’s growth rate, influenced by weather, watering, and fertilization. During peak growing seasons (April-October), St. Augustine grass may need mowing weekly. In cooler months, frequency can be reduced to every two weeks or monthly as growth slows.
Use a sharp mower blade for a clean cut; dull blades tear the grass, leading to frayed, brown tips vulnerable to disease. Sharpen blades regularly, at least once per mowing season. Varying mowing patterns with each cut helps prevent ruts and promotes even growth.