St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
AI-generated identification · may be incorrect
Grass Category
Lawn/Turf Grass
Hardiness Zones
USDA Hardiness Zones 8 through 10, extending into warm parts of Zone 7. Low cold tolerance; undergoes winter dormancy and discoloration when temperatures drop below 50°F and can be damaged by hard freezes.
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Variety / Cultivar
Palmetto or Floratam (common commercial cultivars with wide adaptability and blue-green color)
About This Grass
Coarse-textured warm-season turfgrass forming a dense, carpet-like sward. Bright blue-green to dark green color during active growth, but turns straw-colored (dormant) under frost or extended drought. Unmowed height reaches 6 to 12 inches. Seed heads are flattened spikes arranged unilaterally along a main axis.
Blade Characteristics
Coarse leaf blades (>4mm wide), flat, with rounded, blunt 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. Forms a thick thatch layer if over-fertilized, with moderate drought tolerance and excellent stolon-based recovery.
Growing Information
Origin Region
Native to the coastal regions of the Gulf of Mexico, Caribbean, and tropical regions worldwide. Cultivated widely across the Southern United States and warm coastal areas.
Growth Habit
Aggressively stoloniferous, spreading via thick, flat above-ground stolons that root at the nodes, forming a dense, coarse turf mat.
Sunlight & Water Needs
Performs best in full sun but has the best shade tolerance among warm-season turfgrasses (requires a minimum of 4 hours of direct sunlight). Moderate to high watering needs; requires about 1 inch of water per week. Good drought dormancy but poor sustained drought survival without irrigation.
Mowing & Maintenance
Ideal mowing height ranges from 2.5 to 4 inches. Mow every 7-10 days during the growing season. Medium maintenance level requiring 2-4 lbs N per 1000 sq ft annually. Regular dethatching and core aeration may be needed due to thick thatch production.
Special Characteristics
Good shade tolerance for a warm-season grass, moderate salt tolerance (ideal for coastal properties), poor wear tolerance compared to Bermuda or Zoysia. Susceptible to chinch bugs, sod webworms, and large patch fungus.
Ecological Information
Introduced and naturalized in many tropical and subtropical areas. Provides good soil stabilization and erosion control on coastal soils, but can form dense monocultures that outcompete native understory vegetation if left unmanaged.