St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, Subfamily Panicoideae, Tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Likely 'Floratam' or 'Palmetto' based on commonality and blade width
Hardiness Zones
USDA Hardiness Zones 8-11; poor cold tolerance; enters dormancy (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 via thick, creeping stolons. Seed heads are inconspicuous, appearing as short, thick spikes embedded in the fleshy stem.
Blade Characteristics
Coarse blade width (8-10mm), flat shape with a distinct boat-shaped or rounded tip. Vernation is folded in the bud. The ligule is a short fringe of hairs, and auricles are absent. The collar is continuous and somewhat constricted.
Root System
Fibrous and relatively shallow compared to Centipede but utilizes extensive stolons for coverage; high thatch-forming tendency; moderate establishment speed from sod or plugs.
Growing Information
Origin Region
Native to coastal regions of the Americas, Caribbean, and Africa; thrives in tropical and subtropical climates
Growth Habit
Stoloniferous (spreads via above-ground runners), forming a dense, coarse mat
Sunlight & Water Needs
Partial Sun to Full Sun; best shade tolerance among warm-season grasses (minimum 4-5 hours); high water requirement, low to moderate drought tolerance; prefers pH 5.0-8.5.
Mowing & Maintenance
High maintenance; ideal mowing height 2.5–4.0 inches; requires frequent fertilization (2-4 lbs N per 1000 sq ft/year); prone to thatch buildup needing annual vertical mowing.
Special Characteristics
Excellent salt tolerance (ideal for coastal lawns); moderate wear tolerance; susceptible to Chinch Bugs and Large Patch (Rhizoctonia); good weed suppression due to density.
Ecological Information
Introduced/Naturalized in the US; provides soil stabilization in sandy coastal areas; low wildlife value; not considered invasive in managed landscapes but can escape in wetlands.