St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Palmetto or Floratam
Hardiness Zones
Thrives in USDA Hardiness Zones 8 through 10. Sensitive to heavy frosts and prolonged freezing temperatures.
About This Grass
Forms a thick, carpet-like turf with coarse texture and vibrant green to blue-green color. Mowed height typically ranges from 2.5 to 3.5 inches, while unmowed height can exceed 6 inches. Produces flattened, spike-like seed heads.
Blade Characteristics
Blades are wide (coarse, >4mm), flat, with blunt, rounded tips. Vernation is folded in the bud. Ligule is a fringe of hairs, and auricles are absent. The collar is continuous and broad.
Root System
Moderate root depth with a fibrous root system. High tendency to produce thatch due to heavy stolon production. Establishes moderately quickly from sod or plugs.
Growing Information
Origin Region
Native to tropical and subtropical regions along the Gulf of Mexico and the Caribbean; widely cultivated in the southern United States.
Growth Habit
Stoloniferous, spreading aggressively via above-ground runners (stolons) to form a coarse, dense turf mat.
Sunlight & Water Needs
Requires full sun to moderate shade (most shade-tolerant warm-season grass). Needs regular watering (about 1 inch per week) and has moderate drought tolerance, entering dormancy during severe dry spells.
Mowing & Maintenance
Ideal mowing height is 2.5 to 4 inches using a sharp rotary mower. Requires medium maintenance, including 2 to 4 lbs of nitrogen per 1000 sq ft annually, and periodic dethatching.
Special Characteristics
Good shade tolerance and moderate salt tolerance, making it popular in coastal regions. Fair wear tolerance, but slow to recover from severe damage compared to bermudagrass.
Ecological Information
Introduced/cultivated across the American Sunbelt. Provides good soil stabilization and erosion control in coastal sandy soils. Can become invasive in natural tropical wetlands if escaped.