St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
'Floratam' (most common wide-bladed cultivar with good drought tolerance and lighter green color)
Hardiness Zones
Thrives in USDA Hardiness Zones 8 through 10. Sensitive to hard freezes and goes dormant/turns brown in winter in the colder limits of its range.
About This Grass
Forms a thick, lush, carpet-like turf with coarse texture and a bright to dark green color. Reaches heights of 3 to 6 inches if left unmowed, but maintained at 2.5 to 4 inches. Produces flat, upright seed spikelets on flattened stems.
Blade Characteristics
Blades are coarse (>5mm wide), flat, with blunt, rounded tips. Vernation is folded in the bud. Ligule is a fringe of hairs. Auricles are absent. The collar region is continuous and broad.
Root System
Moderately deep fibrous root system originating from stolon nodes. Establishes quickly from sod or plugs, moderate thatch-forming tendency, forms a very dense sod that limits weed intrusion.
Growing Information
Origin Region
Native to the Gulf of Mexico region, coastal areas of the southeastern United States, the Caribbean, and tropical regions worldwide. Performs best in humid tropical and subtropical climates.
Growth Habit
Aggressively stoloniferous, spreading rapidly via above-ground runners (stolons) to form a dense, coarse-textured sod.
Sunlight & Water Needs
Requires full sun to partial shade (more shade tolerant than most warm-season grasses). Moderate to high watering needs; requires consistent moisture to look its best and has moderate drought tolerance, going dormant in severe drought.
Mowing & Maintenance
Ideal mowing height is 2.5 to 4 inches using a rotary mower. High mowing height is crucial for health. Fertilization needs are moderate to high (2-4 lbs N per 1000 sq ft annually). Requires periodic dethatching and medium-high maintenance.
Special Characteristics
Excellent shade tolerance for a warm-season grass, moderate salt tolerance (good for coastal areas), low wear tolerance compared to Bermuda or Zoysia, prone to chinch bugs and take-all root rot.
Ecological Information
Introduced/cultivated widely in coastal and tropical regions. Provides moderate wildlife habitat and excellent soil stabilization for coastal erosion control due to its dense stolon network.