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' (most common widely adapted cultivar with coarse texture and blue-green color)
Hardiness Zones
USDA Hardiness Zones 8 through 10. Excellent heat tolerance, poor cold tolerance (susceptible to frost damage), and enters winter dormancy in zone 8.
About This Grass
A coarse-textured, aggressive warm-season turfgrass forming a dense, spongy sod. It has a bright to medium-blue green color during the growing season and goes into winter dormancy (turning brown) in the cooler parts of its range. Unmowed height can reach several inches with flattened, upright flowering stems carrying a spiked seed head.
Blade Characteristics
Coarse blades (>4-10mm wide), flat with blunt, rounded tips. Vernation is folded in the bud. Ligule is a fringe of hairs, auricles are absent, and the collar is continuous and broad.
Root System
Moderate depth root system with aggressive stolons rooting at the nodes. Forms a heavy thatch layer over time. Establishes rapidly from sod but slower from plugs; moderate drought tolerance and good wear recovery via stolons.
Growing Information
Origin Region
Native to tropical and subtropical regions along the Gulf of Mexico, the Caribbean, and coastal areas worldwide; thrives in southern United States and humid coastal climates.
Growth Habit
Stoloniferous and rhizomatous, spreading aggressively via above-ground stolons (runners) to form a thick, coarse, carpet-like turf mat.
Sunlight & Water Needs
Requires full sun to partial shade (more shade-tolerant than most warm-season grasses). Needs frequent watering, especially during establishment; moderate to high drought tolerance by entering dormancy, preferring well-drained soils with a pH of 5.5 to 7.5.
Mowing & Maintenance
Mow at 2.5 to 4 inches high. High mowing height is critical for health. Requires moderate to high fertility (2 to 5 lbs N per 1000 sq ft annually depending on region), frequent dethatching due to rapid stolon production, and medium-high overall maintenance.
Special Characteristics
Good shade tolerance for a warm-season grass, moderate salt tolerance (well-suited for coastal regions), poor traffic/wear tolerance compared to Bermuda or Zoysia, prone to chinch bugs and take-all root rot.
Ecological Information
Introduced in many non-native regions for landscaping. Provides basic urban wildlife cover, excellent soil stabilization on coastal sandy soils, and forms monolithic lawns that generally crowd out most weeds when healthy.