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 broad-leaf commercial varieties)
Hardiness Zones
USDA Zones 8-11; poor cold tolerance; enters dormancy and turns brown when temperatures consistently drop below 55°F.
About This Grass
A coarse-textured, low-growing grass with a vibrant dark green color. It remains relatively flat to the ground and forms a carpet-like sod that is effective at crowding out most weeds.
Blade Characteristics
Blade width is coarse (8-10mm); blades are flat with a distinctively rounded or 'boat-shaped' tip; color is medium to dark green; vernation is folded; ligule is a short fringe of hairs; auricles are absent.
Root System
Fibrous and moderately deep, originating from nodes along the thick stolons; prone to heavy thatch buildup; establishes quickly through sod or plugs but not by seed.
Growing Information
Origin Region
Native to the tropical and subtropical regions of the Americas and Africa; common in the Gulf Coast and Southern United States.
Growth Habit
Stoloniferous (spreads via thick, creeping above-ground runners); creates a dense, thick mat.
Sunlight & Water Needs
Prefers full sun but has the best shade tolerance among warm-season grasses; requires 4-6 hours of light; moderate to high water needs; prefers well-drained soil with pH 6.0-7.5.
Mowing & Maintenance
Ideal mowing height is 2.5 to 4.0 inches; requires frequent mowing to prevent thatch; needs 2-4 lbs of nitrogen per 1000 sq ft annually; high maintenance level.
Special Characteristics
Excellent salt tolerance (good for coastal areas); highest shade tolerance for warm-season grass; poor wear tolerance compared to Bermuda; susceptible to Chinch Bugs and Large Patch disease.
Ecological Information
Introduced/Naturalized in the US; provides soil stabilization in sandy coastal areas; low wildlife food value but provides cover; often blended with other warm-season grasses in transition zones.