St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, Subfamily Panicoideae, Tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common or 'Floratam' (likely based on coarse blade and wide stolons visible)
Hardiness Zones
USDA Hardiness Zones 8–11. Poor cold tolerance; turns brown quickly after the first frost and can suffer winter kill in Zone 8a/7b.
About This Grass
A coarse-textured, low-growing grass with a vibrant blue-green to dark-green color. It creates a thick turf mat. In winter, it enters a dormant tan/brown state, as seen in the surrounding dry material in the image. Seed heads are inconspicuous, spike-like racemes.
Blade Characteristics
Coarse width (>4mm); short, flat blades with a distinct rounded/obtuse tip. Vernation is folded in the bud. Ligule is a fringe of short hairs; auricles are absent; collar region is continuous and constricted.
Root System
Fibrous and relatively shallow to moderate depth. High thatch tendency due to thick stolons. Establishment is fast via sod or sprigs but it does not produce viable commercial seeds.
Growing Information
Origin Region
Native to coastal regions of the Gulf of Mexico, Caribbean, and West Africa. Thrives in tropical and subtropical moist climates.
Growth Habit
Stoloniferous (spreads horizontally via thick, above-ground runners). Forms a dense, carpet-like sod through rapid stolon elongation.
Sunlight & Water Needs
Full sun to partial shade (one of the most shade-tolerant warm-season grasses). Requires moderate to high water; low drought tolerance compared to Bermuda grass. Prefers pH 6.0–7.5.
Mowing & Maintenance
Mowing height: 2.5–4.0 inches. Requires frequent mowing during peak summer. Fertilization: 2–4 lbs N per 1000 sq ft per year. High maintenance due to water and pest needs.
Special Characteristics
Excellent shade tolerance for a warm-season grass; high salt tolerance (good for coastal areas). Poor wear tolerance; slow to recover from heavy foot traffic. Susceptible to Chinch bugs and Large Patch (fungus).
Ecological Information
Introduced/Naturalized in the US. Provides soil stabilization in sandy coastal areas. Low wildlife value in turf form. Not considered invasive in most managed landscapes but can aggressively creep into flower beds via stolons.