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' (Common home lawn varieties)
Hardiness Zones
USDA Hardiness Zones 8-11; poor cold tolerance; enters dormancy and turns brown after the first hard frost.
About This Grass
A coarse-textured, low-growing grass that forms a thick sod. It has a vibrant medium-to-dark green color and maintains a dense canopy. Seed heads are inconspicuous, appearing as short, thick spikes (spathe-like spikes) with embedded seeds.
Blade Characteristics
Coarse width (>4mm), folded vernation, flat blades with rounded or blunt tips. Ligule is a fringe of short hairs; auricles are absent. The collar is constricted and distinct.
Root System
Fibrous and stoloniferous; roots produced at the nodes of stolons. Moderate depth with a high tendency to form a thick thatch layer; establishment speed is moderate via sod or plugs.
Growing Information
Origin Region
Native to the Gulf of Mexico region, West Indies, and Western Africa; highly adapted to tropical and subtropical coastal areas.
Growth Habit
Stoloniferous; spreads via thick, creeping above-ground runners (stolons) that root at nodes to form a dense, coarse 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 sun. High water needs; poor drought tolerance compared to Bermuda, prefers well-drained soil with pH 5.0-8.5.
Mowing & Maintenance
Mowing height 2.5–4.0 inches; frequency every 7-10 days. 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), low wear tolerance (does not handle heavy foot traffic well), susceptible to Chinch Bugs and Large Patch disease.
Ecological Information
Native to coastal regions. Provides excellent soil stabilization in sandy coastal areas but can be considered invasive in certain non-native wetland margins. Often used as a mono-stand rather than in mixes.