St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
AI-generated identification · may be incorrect
Grass Category
Lawn/Turf Grass
Hardiness Zones
Thrives in USDA Hardiness Zones 8 through 10. Low cold tolerance and goes dormant (turns brown) with frost. Does not tolerate heavy freezing temperatures.
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Variety / Cultivar
'Palmetto' or 'Floratam' (common commercially available cultivars offering distinct color and shade tolerances)
About This Grass
St. Augustine grass features coarse-textured, broad blades and forms a thick, spongy, dense turf. Its color ranges from blue-green to deep green. It grows aggressively along the ground and typically thrives when maintained at a height of 2.5 to 4 inches.
Blade Characteristics
Coarse blades (>4mm wide), flat shape with blunt, rounded tips. Vernation is folded in the bud. Light to dark green or blue-green color. Features a membranous ligule with a fringe of hairs, continuous collar, and lacks auricles.
Root System
Moderately deep fibrous root system originating from stolon nodes. Forms a thick layer of thatch over time. Establishes relatively quickly from plugs or sod but has moderate drought recovery.
Growing Information
Origin Region
Native to tropical and subtropical coastal regions globally, widely cultivated in the southeastern United States, Gulf Coast, and parts of the Caribbean and South America.
Growth Habit
Stoloniferous, spreading rapidly via robust above-ground runners (stolons) to form a dense, carpet-like turf.
Sunlight & Water Needs
Requires full sun to partial shade; it is the most shade-tolerant warm-season turfgrass. Needs frequent watering and moist soils, with low to moderate drought tolerance (enters dormancy during severe drought). Prefers well-drained soils with a pH between 6.0 and 7.5.
Mowing & Maintenance
Ideal mowing height is 2.5 to 4 inches using a sharp rotary mower. Medium to high maintenance level, requiring regular fertilization (2-4 lbs N per 1000 sq ft annually), frequent watering, and periodic dethatching.
Special Characteristics
Good shade tolerance for a warm-season grass and moderate salt tolerance making it popular in coastal areas. Poor heavy-traffic tolerance compared to Bermuda or Zoysia. Susceptible to chinch bugs, sod webworms, and take-all root rot.
Ecological Information
Introduced/cultivated turfgrass in many regions. Provides standard lawn ecosystem services including soil stabilization, erosion control, and microclimate cooling, though lower wildlife value compared to native prairie grasses.