St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common or 'Floratam' (typical of broad-bladed varieties with purple-tinted stolons)
Hardiness Zones
USDA Hardiness Zones 8-11. Poor cold tolerance; enters dormant brown state when temperatures drop below 55°F consistently.
About This Grass
A coarse-textured, low-growing grass with a vibrant medium-to-dark green color. It spreads via thick, fleshy stolons. Unmowed, it can reach 6-12 inches; maintained, it forms a lush rug-like surface. Seed heads are spike-like racemes with seeds embedded in a thickened rachis.
Blade Characteristics
Coarse width (8-10mm), flat shape with a distinct boat-shaped or rounded tip. Leaf color is medium green. Vernation is folded in the bud. It features a short, fringe-like hairy ligule, no auricles, and a broad, conspicuous collar region.
Root System
Moderately deep fibrous roots originating from stolon nodes. Low thatch tendency if managed well, but can build up. Slow to moderate establishment from plugs or sod (rarely by seed).
Growing Information
Origin Region
Coastal regions of the Gulf of Mexico, Caribbean, and Mediterranean; well-adapted to the Southern United States and California
Growth Habit
Stoloniferous (aggressive above-ground creepers), forming a thick, dense sod
Sunlight & Water Needs
Partial Sun to Full Sun (one of the most shade-tolerant warm-season grasses); needs at least 4-5 hours of sun. Requires moderate to high watering; low drought tolerance compared to Bermuda.
Mowing & Maintenance
Ideal height: 2.5 to 4.0 inches. Frequency: weekly during peak growth. Fertilization: 2-4 lbs N/1000 sq ft/year. Low to Medium maintenance level.
Special Characteristics
Excellent shade tolerance for a warm-season grass; high salt tolerance (good for coastal areas); poor wear tolerance; susceptible to Chinch Bugs and Large Patch (fungus).
Ecological Information
Native to coastal tropics/subtropics. Provides excellent soil stabilization and erosion control. Not considered invasive in managed landscapes but can displace native flora in sensitive coastal dunes.