St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4
Grass Family
Poaceae, Subfamily Panicoideae, Tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Likely 'Floratam' or 'Palmetto' (Standard coarse-textured varieties common in home lawns)
Hardiness Zones
USDA Zones 8-11. Excellent heat tolerance; very poor cold tolerance. Goes dormant and turns brown when soil temperatures drop below 55°F.
About This Grass
A coarse-textured, low-growing grass with a vibrant medium-to-dark green color. It forms a thick sod and typically remains under 12 inches if unmowed. Seed heads are inconspicuous, appearing as short, thick spikes (racemes) with seeds embedded in the rachis.
Blade Characteristics
Coarse width (>4mm), flat blades with a broad, rounded or 'blunt' tip. Color is typically medium-to-dark green. Vernation is folded in the bud. It features a short, hairy ligule, no auricles, and a distinct constricted collar region.
Root System
Fibrous and relatively shallow compared to bunch grasses, but anchored by thick surface stolons. Forms heavy thatch; has a moderate establishment speed when plugged or sodded; poor wear recovery once damaged.
Growing Information
Origin Region
Native to West Indies, Africa, and the Gulf Coast/Florida regions; well-adapted to tropical and subtropical coastal climates.
Growth Habit
Stoloniferous (spreads aggressively via thick, above-ground runners); forms a dense, carpet-like mat.
Sunlight & Water Needs
Partial Sun to Full Sun (one of the most shade-tolerant warm-season grasses); needs at least 4-5 hours of direct sun. High water needs; low drought tolerance (wilts quickly without moisture). Prefers well-drained, slightly acidic to neutral soils.
Mowing & Maintenance
Maintain at 2.5 to 4.0 inches; mow every 7-10 days during peak growth. Fertilize with 2-4 lbs N per 1000 sq ft per year. High maintenance level due to water, pest (Chinch bug), and dethatching needs.
Special Characteristics
Excellent shade tolerance for a warm-season grass; high salt tolerance (ideal for coastal areas); poor traffic tolerance; highly susceptible to Large Patch (fungus) and Chinch bugs.
Ecological Information
Introduced/Naturalized in the US. Provides soil stabilization but can be aggressive in native environments. Low wildlife food value but provides cover for small invertebrates in the thick thatch layer.