St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, Panicoideae, Tribe Paniceae
Grass Category
Lawn/Turf Grass, Erosion Control
Variety / Cultivar
Common St. Augustine (likely, based on leaf width and internode color)
Hardiness Zones
USDA Zones 8-11; poor cold tolerance; enters dormancy 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 is highly recognizable by its broad, blunt-tipped blades and distinctive creeping stolons. Seed heads are spike-like racemes with seeds embedded in a thickened rachis.
Blade Characteristics
Coarse blade width (>4mm), folded vernation, flat shape with a distinctly boat-shaped or rounded tip. Ligule is a fringe of short hairs; auricles are absent; collar region is continuous and narrowed.
Root System
Moderately deep fibrous root system originating from stolon nodes; high thatch-forming tendency; moderate establishment speed from sod or plugs; good wear recovery via stolon lateral growth.
Growing Information
Origin Region
Coastal regions of the Gulf of Mexico, Caribbean, and Mediterranean; adapted to subtropical and tropical climates
Growth Habit
Stoloniferous (spreads aggressively via thick above-ground runners/stolons); forms a dense, carpet-like mat
Sunlight & Water Needs
Partial sun to full sun; one of the most shade-tolerant warm-season grasses (needs 4-5 hours min). High water needs; poor drought tolerance compared to Bermuda, prefers moist, well-drained soils with pH 5.0-8.5.
Mowing & Maintenance
Mowing height 2.5 to 4.0 inches; frequency based on growth (weekly in summer); fertilization 2-4 lbs N per 1000 sq ft per year; high maintenance level; prone to Chinch bugs and Gray Leaf Spot.
Special Characteristics
Excellent shade tolerance for a warm-season grass; high salt tolerance (good for coastal areas); poor traffic tolerance due to fleshy stolons; competitive against weeds when dense.
Ecological Information
Introduced/Naturalized in the Southern US; provides soil stabilization for coastal dunes; low wildlife food value but provides cover for small invertebrates; can be invasive in sensitive wetland margins.