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. Excellent heat tolerance, poor cold tolerance (suffers freeze damage below 25°F), goes dormant and turns brown in winter in cooler parts of its range.
Grass Family
Poaceae, subfamily Panicoideae
Variety / Cultivar
Palmetto or Floratam (commonly cultivated turf varieties)
About This Grass
A coarse-textured, dense, warm-season turfgrass with a bright to dark green color. Forms a thick sod with flat blades and blunt tips. Unmowed height reaches 6 to 12 inches, maintained at 2 to 3 inches. Produces flat, spike-like seed heads.
Blade Characteristics
Coarse blades (>4mm wide), flat shape with rounded or blunt tips, bright blue-green to dark green color, folded vernation in the bud, prominent veins on the upper surface, membranous ligule with a fringe of hairs, absent auricles, and a continuous collar region.
Root System
Shallow to moderate fibrous root system, forming thick thatch easily if over-fertilized. Fast-growing stolons establish quickly from sod or plugs, moderate drought tolerance with poor recovery compared to some warm-season grasses.
Growing Information
Origin Region
Native to coastal regions of the Gulf of Mexico, Caribbean, and tropical regions worldwide. Performs best in warm, humid subtropical and tropical climates.
Growth Habit
Stoloniferous, spreading vigorously via above-ground runners (stolons) to form a thick, coarse turf mat.
Sunlight & Water Needs
Requires full sun to partial shade (more shade tolerant than most warm-season grasses, needing at least 4 hours of sun). High water requirement during active growth, moderate drought tolerance by entering dormancy. Thrives in moist, well-draining soils with a pH between 6.0 and 7.5.
Mowing & Maintenance
Ideal mowing height is 2.5 to 3.5 inches with a rotary mower. Mowed weekly during active summer growth. Fertilization requires 2 to 4 lbs N per 1000 sq ft annually. High maintenance level due to disease susceptibility, thatch management, and weed control.
Special Characteristics
Moderate wear tolerance (lower than Bermuda or Zoysia), susceptible to Take-All Root Rot, chinch bugs, and sod webworms. Good salt tolerance making it ideal for coastal areas. Poor cold tolerance. Excellent erosion control.
Ecological Information
Introduced and naturalized in many tropical and subtropical regions. Provides ground cover and micro-habitat for small insects and urban wildlife. Helps stabilize coastal soils and filter runoff, but can be invasive in native tropical wetlands.