St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Floratam (most common coarse-textured cultivar with purple-tinted stolons)
Hardiness Zones
USDA Hardiness Zones 8 through 10. Highly sensitive to freezing temperatures and enters winter dormancy in the colder portions of its range.
About This Grass
Forms a dense, carpet-like turf with coarse texture and blue-green to dark green coloration. Typically maintained at a height of 2.5 to 4 inches. Left unmowed, it can grow up to 6-12 inches tall with upright seed stalks bearing flat spikes.
Blade Characteristics
Blades are coarse (>5mm wide), flat, with blunt, rounded tips. Vernation is folded in the bud. Ligule is a fringe of hairs. Collars are continuous and broad, and auricles are absent.
Root System
Moderately deep fibrous root system originating from nodes along the stolons. Establishes quickly from sod, forms a moderate thatch layer, and provides fair drought tolerance with moderate-to-high recovery via stolons.
Growing Information
Origin Region
Native to tropical and subtropical regions along the Gulf of Mexico, the Caribbean, and the Mediterranean; widely cultivated throughout the southern United States and coastal regions worldwide.
Growth Habit
Stoloniferous, spreading rapidly via thick surface runners (stolons) to form a dense, coarse-textured turf mat.
Sunlight & Water Needs
Performs best in full sun, but is the most shade-tolerant of all warm-season grasses (tolerates down to 4 hours of direct sun). Requires regular watering (1 inch per week) and thrives in moist, well-draining soils with a pH between 6.0 and 7.5.
Mowing & Maintenance
Ideal mowing height is 2.5 to 4 inches using a sharp rotary mower. Requires medium-to-high maintenance, regular fertilization (2 to 4 lbs N per 1000 sq ft annually), and periodic dethatching.
Special Characteristics
Excellent shade tolerance and good salt tolerance making it popular for coastal regions. Moderate wear tolerance; slower to recover from heavy traffic than Bermuda or Zoysia due to coarse stolons. Susceptible to chinch bugs and take-all root rot.
Ecological Information
Introduced/cultivated across southern landscapes. Provides good soil stabilization and erosion control in sandy coastal soils. Serves as a wildlife habitat for various insects and small urban wildlife.