St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4
Grass Family
Poaceae, Subfamily Panicoideae, Tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common St. Augustine (likely 'Floratam' or 'Palmetto' based on blade width and stolon presence)
Hardiness Zones
USDA Zones 8-11. Poor cold tolerance; enters dormant brown state when temperatures drop below 55°F; susceptible to winter kill in northern transition zones.
About This Grass
Coarse-textured, low-growing turf with a creeping habit. It features wide, blunt blades and thick, compressed stolons. It is bright to dark green in color and forms a very dense sod that crowds out most weeds.
Blade Characteristics
Coarse (8-10mm wide), flat blades with a distinct rounded or blunt tip. Vernation is folded in the bud. Ligule is a fringe of short hairs; auricles are absent. The collar region is continuous and narrowed.
Root System
Deeply fibrous roots originating from stolon nodes; low thatch tendency but thick organic layer; establishment is moderate via sod or plugs rather than seed.
Growing Information
Origin Region
Native to coastal regions of the Gulf of Mexico, Caribbean, and Mediterranean; well-adapted to tropical and subtropical climates.
Growth Habit
Stoloniferous; spreads via thick, creeping above-ground stolons that form a dense, carpet-like mat.
Sunlight & Water Needs
Partial sun to full sun (4-6 hours minimum); high water needs; poor drought tolerance compared to Bermuda, but best shade tolerance among warm-season grasses. Prefers moist, well-drained soils with pH 6.0-7.5.
Mowing & Maintenance
High maintenance. Recommended mowing height of 2.5 to 4.0 inches. Requires frequent mowing and 2-4 lbs of Nitrogen per 1000 sq ft annually. Sensitive to certain herbicides.
Special Characteristics
Excellent shade tolerance for a warm-season grass; high salt tolerance (ideal for coastal areas); poor wear tolerance; susceptible to Large Patch (Brown Patch) and Gray Leaf Spot; high susceptibility to Chinch Bugs.
Ecological Information
Introduced/Naturalized in the US. Provides excellent soil stabilization and erosion control. Low wildlife food value but provides cover. Can be invasive in sensitive wetland margins due to aggressive stolon growth.