St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
'Floratam' (a popular widely cultivated cultivar known for its coarser texture, larger leaves, and bright green color)
Hardiness Zones
USDA Hardiness Zones 8 through 10. Highly sensitive to freezing temperatures, goes dormant and turns brown with frost, excellent heat and humidity tolerance.
About This Grass
Forms a dense, coarse-textured, bright to blue-green turf. Height when unmowed can reach 6 to 12 inches, but typically maintained at 2.5 to 4 inches. Produces flat, upright seed heads on a spike-like terminal panicle at maturity.
Blade Characteristics
Coarse texture with wide blades (typically 4-10 mm wide), flat shape, blunt or rounded tips, bright green to blue-green color. Rolled in the bud (vernation). Features a very short membranous ligule with a fringe of hairs, absent auricles, and a continuous collar.
Root System
Moderate root depth with a fibrous root system anchored by robust stolons. Moderate to high thatch-forming tendency, establishes quickly from sod or plugs, moderate drought tolerance once established.
Growing Information
Origin Region
Native to the Gulf of Mexico region, coastal areas of the southeastern United States, West Indies, and tropical regions worldwide. Well-adapted to coastal and subtropical climates.
Growth Habit
Stoloniferous (spreads aggressively via above-ground runners called stolons) forming a thick, dense, carpet-like sod.
Sunlight & Water Needs
Requires full sun to partial shade (most shade-tolerant warm-season grass, needing a minimum of 4 hours of direct sunlight). Moderate to high water needs; moderate drought tolerance by entering dormancy during prolonged dry spells.
Mowing & Maintenance
Ideal mowing height is 2.5 to 4 inches using a sharp rotary mower. Medium maintenance level requiring regular fertilization (2 to 4 lbs N per 1000 sq ft annually), occasional dethatching, and consistent watering.
Special Characteristics
Moderate traffic and wear tolerance (recovers slower than Bermuda), poor cold tolerance, high salt tolerance making it ideal for coastal areas, good shade tolerance relative to other warm-season grasses.
Ecological Information
Introduced/cultivated widely in tropical and subtropical regions. Provides good soil stabilization and erosion control in coastal areas. Low wildlife food value compared to native grasses, primarily utilized for residential and commercial turf landscaping.