St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Lawn/Turf Grass and Erosion Control
Variety / Cultivar
'Floratam' (or common St. Augustine), featuring coarse texture and blue-green color
Hardiness Zones
Thrives in USDA Hardiness Zones 8 through 10; poor cold tolerance (susceptible to frost damage and winter dormancy discoloration); not suitable for northern cool-season zones
About This Grass
Forms a coarse-textured, dense, bright to blue-green turf with flat blades and blunt tips. Unmowed height reaches 6 to 12 inches. Distinctive flat, thick stolons and spike-like seed heads.
Blade Characteristics
Coarse width (>4mm), flat shape, rounded or blunt tip, blue-green to bright green color, folded vernation in the bud, prominent ligule consisting of a fringe of hairs, and absent auricles
Root System
Shallow to moderately deep fibrous root system originating from stolon nodes; moderate establishment speed from sod or plugs; forms a thick thatch layer over time
Growing Information
Origin Region
Native to the Gulf of Mexico region, coastal areas of the Americas, and parts of Africa; well-adapted to tropical and subtropical climates
Growth Habit
Stoloniferous, spreading aggressively via thick above-ground runners (stolons) to form a dense, coarse turf mat
Sunlight & Water Needs
Requires full sun to partial shade (more shade tolerant than most warm-season grasses); high watering needs during dry spells; moderate drought tolerance with dormancy during extreme drought; prefers moist, well-draining soils with slightly acidic to neutral pH
Mowing & Maintenance
Ideal mowing height is 2.5 to 4 inches; high maintenance level requiring regular mowing, moderate to high fertilization (2 to 5 lbs N per 1000 sq ft annually), and periodic dethatching due to rapid stolon growth
Special Characteristics
Moderate wear tolerance (lower than Bermuda or Zoysia), poor cold tolerance, excellent salt tolerance (ideal for coastal regions), good shade tolerance relative to other warm-season grasses, and susceptible to chinch bugs and take-all root rot
Ecological Information
Introduced and naturalized widely in warm coastal regions; provides good soil stabilization and erosion control on sandy coastal soils; low wildlife food value compared to native prairies; forms dense monocultures that crowd out weeds