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' (known for large coarse blades, excellent drought tolerance, and bright green color)
Hardiness Zones
Thrives in USDA Hardiness Zones 8 through 10. Susceptible to freeze damage below 20°F (-6°C), going into winter dormancy in cooler parts of its range.
About This Grass
Forms a dense, carpet-like turf with coarse, flat blades. Typically maintained at 2 to 3 inches in height. Color ranges from blue-green to bright apple-green depending on the cultivar and fertility. Seed heads are flat spikes with spikelets embedded alternately on one side of the axis.
Blade Characteristics
Coarse blades, generally 4 to 10 mm wide, flat with blunt or rounded tips. Vernation is folded in the bud. Ligule is a fringe of hairs. Auricles are absent. Collar is continuous and broad.
Root System
Moderately deep fibrous root system originating from nodes along the stolons. Forms a moderate to heavy thatch layer over time. Establishes rapidly from sod or plugs.
Growing Information
Origin Region
Native to coastal regions of the Gulf of Mexico, Caribbean, and tropical regions worldwide. Best adapted to warm, humid subtropical and tropical climates.
Growth Habit
Aggressively stoloniferous, forming a thick, coarse-textured mat by spreading via above-ground runners (stolons).
Sunlight & Water Needs
Requires full sun to moderate shade (more shade-tolerant than most warm-season grasses). Needs regular watering (1 inch per week) and has moderate to low drought tolerance, entering dormancy during extended dry spells.
Mowing & Maintenance
Mow at 2.5 to 3.5 inches with a sharp rotary mower. Requires medium to high maintenance, needing 2 to 4 lbs of nitrogen per 1000 sq ft annually, regular irrigation, and periodic dethatching.
Special Characteristics
Good salt tolerance (often used in coastal areas), moderate weed suppression due to dense mat, low traffic tolerance compared to Bermuda grass, susceptible to chinch bugs and Take-All Root Rot.
Ecological Information
Introduced and naturalized in many tropical/subtropical coastal zones. Provides soil stabilization and erosion control on sandy coastal soils. Limited wildlife forage value compared to native grasses.