St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
'Floratam' (coarse texture, bright green color, purple stolons)
Hardiness Zones
USDA Hardiness Zones 8 through 10. Excellent heat tolerance, poor cold tolerance (susceptible to frost damage and enters winter dormancy below 50 degrees Fahrenheit).
About This Grass
Forms a lush, dense, coarse-textured turf with broad flat blades and a bright green to blue-green color. Mows into a carpet-like surface when well-maintained at higher heights. Seed heads are flattened spikes with spikelets embedded in a zig-zag axis.
Blade Characteristics
Coarse width (>4mm), flat shape with rounded tips, bright green to blue-green color, rolled in the bud (vernation). Membranous ligule with a fringe of hairs, continuous collar, and absent auricles.
Root System
Moderately deep fibrous root system originating from nodes along the thick stolons. Moderate thatch-forming tendency, fast establishment from plugs or sod, forms a dense sod that resists weed invasion.
Growing Information
Origin Region
Native to the Gulf of Mexico region, coastal areas of the southeastern United States, and the Caribbean. Thrives in tropical and subtropical climates.
Growth Habit
Stoloniferous, spreading aggressively via robust above-ground runners (stolons) to form a dense, thick mat.
Sunlight & Water Needs
Requires full sun to partial shade (more shade-tolerant than most warm-season grasses, needing at least 4 hours of direct sun). High water needs during active growth, moderate drought tolerance by entering dormancy, prefers well-drained soils with a pH of 6.0 to 7.5.
Mowing & Maintenance
Ideal mowing height is 2.5 to 4 inches using a sharp rotary mower. Medium-high maintenance level requiring regular fertilization, frequent watering, and periodic dethatching.
Special Characteristics
Moderate wear and traffic tolerance (lower than Bermuda or Zoysia), susceptible to chinch bugs and take-all root rot, good salt spray tolerance making it ideal for coastal lawns, poor cold tolerance, excellent shade tolerance for a warm-season turf.
Ecological Information
Introduced and widely naturalized in tropical regions worldwide. Provides moderate wildlife cover, excellent soil stabilization and erosion control in coastal regions, and acts as a dense ground cover that crowds out weeds.