St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
'Floratam' or 'Palmetto' (widely cultivated cultivars known for broad leaves and good color)
Hardiness Zones
Thrives in USDA Hardiness Zones 8 through 10. Excellent heat tolerance, poor cold tolerance (goes dormant and can suffer winter damage below freezing).
About This Grass
Forms a lush, dense, blue-green to dark green turf with a coarse texture. Typically maintained at 2.5 to 4 inches. When unmowed, it can grow up to 6-12 inches tall with flat, thick stems and a distinctive spike-like seed head.
Blade Characteristics
Coarse blades wider than 4mm, flat shape with rounded or blunt tips. Vernation is folded in the bud. The ligule is a fringe of hairs, and auricles are absent. The collar region is continuous and broad.
Root System
Moderately deep fibrous root system originating from nodes on the stolons. Spreads quickly via surface runners, forms a moderate thatch layer, and establishes quickly from sod.
Growing Information
Origin Region
Native to tropical regions along the Gulf of Mexico, the Caribbean, and coastal areas worldwide; thrives in warm, humid subtropical climates.
Growth Habit
Stoloniferous, spreading rapidly via thick, above-ground runners (stolons) to form a dense, coarse-textured turf mat.
Sunlight & Water Needs
Performs best in full sun but has the best shade tolerance among warm-season grasses. Requires moderate to high watering; moderate drought tolerance entering dormancy during severe dry spells.
Mowing & Maintenance
Ideal mowing height is 2.5 to 4 inches using a rotary mower. Requires medium maintenance, including 2 to 4 lbs N per 1000 sq ft annually, regular watering, and occasional dethatching.
Special Characteristics
Good salt tolerance making it ideal for coastal regions. Moderate wear tolerance, but slower recovery from heavy damage compared to bermudagrass. Susceptible to chinch bugs and take-all root rot.
Ecological Information
Introduced/cultivated turfgrass in many suburban landscapes. Provides limited wildlife value compared to native grasses, but offers excellent soil stabilization and erosion control in coastal sandy soils.