St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4
Grass Family
Poaceae, Panicoideae, Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Likely 'Floratam', 'Palmetto', or 'Raleigh' based on blade width and growth habit
Hardiness Zones
USDA Zones 8-11; poor cold tolerance; enters dormant straw-colored state when temperatures drop below 55°F; highly heat tolerant.
About This Grass
A coarse-textured, low-growing grass with a distinctive medium to dark green color. It forms a thick sod that crowds out weeds. It typically reaches 6-12 inches if unmowed, featuring short, spike-like seed heads.
Blade Characteristics
Coarse blades (8-10mm wide), flat to slightly folded shape with a distinctly rounded/blunt tip; light to dark green color; folded vernation; ligule is a short fringe of hairs; auricles are absent; compressed, wide collar region.
Root System
Fibrous and moderately deep; primarily spreads via thick, creeping stolons; slow to moderate establishment from plugs/sod; heavy thatch former; moderate wear recovery due to stoloniferous nature.
Growing Information
Origin Region
Native to coastal regions of the Gulf of Mexico, Caribbean, and West Africa; thrives in tropical and subtropical climates
Growth Habit
Stoloniferous (spreads aggressively via thick above-ground runners), forming a dense, coarse-textured mat
Sunlight & Water Needs
Partial Sun to Full Sun (one of the most shade-tolerant warm-season grasses); needs minimum 4-6 hours of light; high water requirements; moderate drought tolerance but wilts quickly without moisture; prefers slightly acidic to neutral pH (5.0-8.5).
Mowing & Maintenance
Ideal height: 2.5–4.0 inches; weekly mowing; 2-4 lbs Nitrogen per 1000 sq ft per year; high maintenance due to potential for Large Patch disease and Chinch Bug infestations; requires regular dethatching.
Special Characteristics
Excellent shade tolerance for a warm-season grass; high salt tolerance (good for coastal areas); poor traffic tolerance compared to Bermuda; susceptible to Gray Leaf Spot and Chinch Bugs.
Ecological Information
Introduced species in many areas; provides soil stabilization in sandy coastal environments; can be invasive in native wetlands; often grown as a monoculture; compatible with some broadleaf groundcovers but usually grown alone.