St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, Panicoideae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Likely 'Floratam' or 'Palmetto' based on blade width and common residential use; 'Floratam' is noted for long stolons and lack of cold hardiness.
Hardiness Zones
USDA Hardiness Zones 8-11. Very poor cold tolerance; will suffer leaf death or total kill in prolonged freezing temperatures.
About This Grass
A low-growing, coarse-textured turfgrass with a creeping growth habit. It maintains a vibrant dark green color in summer and goes dormant (tan/brown) in frost-prone winters. It forms a thick carpet that crowds out most weeds.
Blade Characteristics
Coarse (8-10mm wide), flat blades with a distinct rounded (blunt) tip. Features folded vernation 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, though stolons provide significant surface anchoring. It has a high thatch-forming tendency and moderate establishment speed from sod or plugs.
Growing Information
Origin Region
Native to the coastal regions of the Gulf of Mexico, the Caribbean, and West Africa; adapted to tropical and subtropical climates.
Growth Habit
Stoloniferous (spreads aggressively via thick, above-ground runners); forms a dense, coarse-textured mat.
Sunlight & Water Needs
Partial Sun to Full Sun; one of the most shade-tolerant warm-season grasses (needs 4-6 hours). High water requirement; poor drought tolerance compared to Bermuda, preferring moist, well-drained soils with pH 6.0-7.5.
Mowing & Maintenance
Ideal height 3.5 to 4.0 inches. Mowing frequency is weekly during peak growth. Requires 2-4 lbs of Nitrogen per 1000 sq ft annually. High maintenance level 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 due to succulent stolons; susceptible to Chinch Bugs and Large Patch (fungus).
Ecological Information
Introduced/Naturalized in the US. Provides soil stabilization in coastal sandy areas. Not considered highly invasive in managed landscapes but can escape into moist riparian zones in tropical climates.