St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Floratam (most common coarse-textured variety with a bright blue-green color)
Hardiness Zones
Thrives in USDA Hardiness Zones 8 through 10. Susceptible to freeze damage below freezing temperatures, going dormant and turning brown in winter in the cooler limits of its range.
About This Grass
A coarse-textured, dense, low-growing warm-season turfgrass with broad flat blades and blunt tips. It forms a lush, carpet-like lawn ranging from light to dark blue-green. Unmowed, it can reach heights of 6 to 12 inches. Produces flattened seed spikes.
Blade Characteristics
Blades are coarse (>4mm wide), flat, with blunt, rounded tips. Vernation is folded in the bud. Color is typically bright blue-green to medium green. Ligule is a fringe of hairs, auricles are absent, and the collar region is continuous.
Root System
Moderately deep fibrous root system originating from thick surface stolons. Moderate thatch-forming tendency. Establishes relatively quickly from sod or plugs, forming a tight sod that has fair drought tolerance and good wear recovery through stolon growth.
Growing Information
Origin Region
Native to coastal regions of the Gulf of Mexico, Caribbean, and Mediterranean; widely cultivated throughout the southeastern and coastal United States
Growth Habit
Stoloniferous, spreading rapidly via thick surface runners (stolons) to form a dense, coarse mat
Sunlight & Water Needs
Requires full sun to partial shade (more shade tolerant than most warm-season grasses). Needs regular watering and moderate irrigation to maintain green color; has moderate drought tolerance by entering dormancy during extreme dry spells. Prefers moist, fertile soils with a pH between 6.0 and 7.5.
Mowing & Maintenance
Ideal mowing height is 2.5 to 4 inches using sharp rotary blades to prevent tearing. Requires moderate to high maintenance, including regular fertilization (2 to 4 lbs N per 1000 sq ft annually), occasional dethatching, and frequent watering during growing season.
Special Characteristics
Excellent shade tolerance compared to other warm-season grasses and good salt tolerance making it ideal for coastal areas. Moderate traffic tolerance, but prone to chinch bugs, take-all root rot, and gray leaf spot. Recovers well from damage via stolons.
Ecological Information
Introduced and naturalized in tropical and subtropical regions worldwide. Provides good soil stabilization and erosion control on coastal sandy soils. Dense turf effectively crowds out many weeds. Offers moderate habitat value for small urban wildlife.