St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4
Grass Family
Poaceae, subfamily Panicoideae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
'Floratam', a widely used cultivar known for its coarse texture, blue-green color, and good resistance to St. Augustine Decline (SAD) virus.
Hardiness Zones
USDA Hardiness Zones 8 through 10. Low cold tolerance compared to other warm-season grasses; susceptible to freeze damage below 20°F.
About This Grass
Forms a thick, carpet-like turf with coarse-textured, flat blades. Typically maintained at 2.5 to 3 inches in height. Color is typically medium to dark green, turning brown during winter dormancy in cooler parts of its range.
Blade Characteristics
Blades are coarse (>4mm wide), flat, with blunt, rounded tips. Vernation is folded in the bud. Ligule is a fringe of hairs. Auricles are absent. The collar region is continuous and broad.
Root System
Moderate depth, fibrous root system accompanied by extensive surface stolons. Tends to build up thatch moderately fast if over-fertilized. Establishes quickly from sod or plugs.
Growing Information
Origin Region
Native to tropical and subtropical regions along the Gulf of Mexico, the Caribbean, and coastal areas worldwide; performs best in warm, humid climates.
Growth Habit
Stoloniferous, spreading aggressively via above-ground runners (stolons) to form a dense, coarse-textured turf mat.
Sunlight & Water Needs
Requires full sun to partial shade (more shade-tolerant than most warm-season grasses). High water requirement during dry periods; moderate drought tolerance by entering dormancy.
Mowing & Maintenance
Ideal mowing height is 2.5 to 4 inches using a rotary mower. Requires medium maintenance including regular fertilization (2-4 lbs N per 1000 sq ft annually) and occasional dethatching.
Special Characteristics
Moderate to low wear tolerance due to its fleshy stolons. Poor recovery from heavy traffic. Good salt tolerance, making it popular for coastal properties.
Ecological Information
Introduced and naturalized in many warm coastal regions. Provides soil stabilization and erosion control in coastal sandy soils. Low wildlife foraging value compared to native prairie grasses.