St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Lawn/Turf Grass, Coastal and Shade Turf
Variety / Cultivar
Commonly 'Palmetto', 'Floratam', or 'Raleigh', known for distinct green coloring and cold or shade tolerances depending on selection
Hardiness Zones
Thrives in USDA Hardiness Zones 8 through 10. Excellent heat tolerance, poor extreme cold tolerance (goes dormant and can suffer freeze damage below freezing).
About This Grass
Forms a dense, coarse-textured, blue-green to bright green carpet with flat, wide leaf blades and blunt tips. Can grow quite tall if unmoved, but maintained between 2.5 to 4 inches. Produces flattened seed spikes.
Blade Characteristics
Coarse texture (>4mm wide), flat shape with rounded, blunt tips. Light green to blue-green color. Rolled in the bud (vernation). Short membranous ligule with a fringe of hairs, continuous collar, and absent auricles.
Root System
Moderately deep fibrous root system originating from nodes along the stolons. Forms a spongy thatch layer quickly. Moderate establishment speed from sod or plugs.
Growing Information
Origin Region
Native to tropical regions along the Gulf of Mexico, the Caribbean, and coastal areas globally; widely cultivated in the southern United States and tropical climates
Growth Habit
Aggressively stoloniferous, spreading via thick above-ground runners (stolons) to form a dense, coarse turf mat
Sunlight & Water Needs
Requires full sun to partial shade; highly shade-tolerant compared to most warm-season grasses. Needs regular watering, moderate to high moisture, with good drought dormancy tendencies.
Mowing & Maintenance
Ideal mowing height is 2.5 to 4 inches using a sharp rotary mower. Requires moderate to high maintenance, frequent mowing during peak growing season, and regular fertilization (2-5 lbs N per 1000 sq ft annually).
Special Characteristics
Moderate wear tolerance but slow to recover from heavy damage due to stolon-only spreading. Good salt tolerance (ideal for coastal regions). Moderate shade tolerance. Prone to chinch bugs and large patch disease.
Ecological Information
Introduced/cultivated turfgrass in many non-native regions. Provides good erosion control on coastal soils and slopes. Low wildlife forage value compared to native grasses, primarily utilized for residential and commercial lawns.