St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
'Floratam' (a common coarse-textured cultivar widely used in the southern US)
Hardiness Zones
Thrives in USDA Hardiness Zones 8 through 10. Low cold tolerance and enters winter dormancy in cooler portions of its range.
About This Grass
Forms a lush, dense, blue-green to dark green turf with a coarse texture. Typically maintained at heights between 2.5 and 4 inches. Unmowed, it can grow taller and produces flattened, spike-like seed heads.
Blade Characteristics
Blades are broad (coarse, >4-5mm wide), flat, with blunt, rounded tips. Vernation is folded in the bud. The ligule is a fringe of hairs, and auricles are absent. The collar region is continuous.
Root System
Moderately deep fibrous root system originating from nodes along the thick stolons. Forms a spongy sod, has a medium thatch tendency, and establishes quickly from sod.
Growing Information
Origin Region
Native to tropical and subtropical regions around the Gulf of Mexico, the Caribbean, and coastal areas worldwide. Thrives in warm, humid coastal climates.
Growth Habit
Stoloniferous, spreading aggressively via above-ground runners (stolons) to form a dense, coarse turf mat.
Sunlight & Water Needs
Requires full sun to partial shade (more shade-tolerant than most warm-season grasses). Needs regular watering, moderate drought tolerance, and prefers well-drained soils with a pH of 6.0 to 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) and occasional dethatching.
Special Characteristics
Moderate wear tolerance, poor cold tolerance, excellent shade tolerance compared to other warm-season turfgrasses, good salt spray tolerance, and moderate drought recovery via stolons.
Ecological Information
Introduced/cultivated across warm coastal regions, provides moderate wildlife cover in residential landscapes, excellent for coastal erosion control due to dense stolon network.