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, with high heat tolerance. Low cold tolerance, going dormant and losing color when temperatures drop below 50°F (10°C).
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Variety / Cultivar
'Palmetto' St. Augustine (known for better shade tolerance and semi-dwarf growth habit)
About This Grass
Forms a lush, dense, carpet-like turf with coarse texture and blue-green to deep green color. Mowed height typically maintained between 2.5 and 4 inches. Unmowed, it can grow up to 6 to 12 inches tall with flattened, branching seed stalks.
Blade Characteristics
Coarse blades wider than 4mm (typically 5-10mm wide), flat, with blunt, rounded tips. Folded vernation in the bud. Smooth texture with distinct veins. Short membranous ligule with a fringe of hairs, continuous collar, and absent or very small auricles.
Root System
Shallow to moderately deep fibrous root system originating from nodes along the thick stolons. Moderate to high thatch-forming tendency. Establishes rapidly from sod or plugs. Forms a very dense sod that restricts weed growth.
Growing Information
Origin Region
Native to tropical and subtropical coastal regions around the Gulf of Mexico, Caribbean, and West Africa. Widely cultivated in the southern United States and coastal tropical regions worldwide.
Growth Habit
Stoloniferous, spreading aggressively above ground via thick stolons (runners) to form a dense, coarse-textured turf mat.
Sunlight & Water Needs
Requires full sun to partial shade (more shade-tolerant than most warm-season grasses). Needs frequent watering (1 inch of water per week) to maintain green color and vigor. Moderate drought tolerance, entering dormancy during severe dry spells. Prefers well-drained soils with a pH of 6.0 to 7.5.
Mowing & Maintenance
Ideal mowing height ranges from 2.5 to 4 inches using a sharp rotary mower. Mower frequency depends on growth rate (every 7 to 14 days in peak season). Requires 2 to 4 lbs of nitrogen per 1000 sq ft annually. High maintenance level due to regular watering, fertilization, and occasional dethatching.
Special Characteristics
Moderate wear tolerance (does not recover from heavy traffic as quickly as Bermuda grass). Good salt tolerance making it ideal for coastal properties. Susceptible to chinch bugs, sod webworms, and fungal diseases like take-all root rot and brown patch. Excellent weed-crowding ability when healthy.
Ecological Information
Introduced and naturalized in many tropical and subtropical regions outside its native range. Provides minor wildlife habitat and excellent soil stabilization for coastal erosion control. Filters runoff effectively due to its dense root and stolon mat.