St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
AI-generated identification · may be incorrect
Grass Category
Lawn/Turf Grass
Hardiness Zones
Thrives in USDA Hardiness Zones 8 through 10. Exceptional heat tolerance, but poor cold tolerance, experiencing winter dormancy and potential freeze damage below 25°F (-4°C).
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Variety / Cultivar
Floratam (coarse texture, bright green color, high drought and sun tolerance)
About This Grass
Forms a dense, thick, carpet-like turf with broad, flat blades. Typically maintained at heights between 2.5 to 4 inches, but can grow much taller if left unmowed. Color ranges from medium to dark bluish-green during the active growing season, turning brown and going dormant under frost conditions. Produces a flattened seed spike at maturity.
Blade Characteristics
Blades are coarse (greater than 4mm wide), flat, with rounded tips. Vernation is folded in the bud. The ligule is a fringe of hairs, and auricles are absent. The collar is continuous and broad.
Root System
Moderately deep fibrous root system combined with robust surface stolons. Moderate to high thatch-forming tendency due to rapid stolon production. Establishes relatively quickly from sod or plugs. Forms a very dense, spongy sod that provides good erosion control.
Growing Information
Origin Region
Native to the coastal regions of the Gulf of Mexico, the Caribbean, and along the Mediterranean and Western African coasts. Widely cultivated throughout the southern United States, parts of Australia, and tropical/subtropical regions worldwide.
Growth Habit
Stoloniferous (spreading aggressively above ground via thick runners), forming a dense, coarse-textured turf mat.
Sunlight & Water Needs
Requires full sun to partial shade (more shade-tolerant than most other warm-season grasses, requiring at least 4 hours of direct sunlight). High water requirement to maintain optimal color and growth during dry periods, with moderate drought tolerance entering dormancy when dry.
Mowing & Maintenance
Ideal mowing height ranges from 2.5 to 4 inches using a sharp rotary mower to avoid tearing the coarse blades. Mowed every 7 to 10 days during peak growth. Fertilization requires 2 to 4 lbs N per 1000 sq ft per year. Moderate to high maintenance level, including regular dethatching and watering.
Special Characteristics
Moderate traffic and wear tolerance (recovers more slowly than Bermuda or Zoysia). Good salt tolerance, making it popular in coastal environments. Excellent shade tolerance relative to warm-season grasses. Susceptible to chinch bugs, sod webworms, and fungal diseases like take-all root rot and brown patch.
Ecological Information
Introduced and naturalized in many tropical and subtropical regions outside its native range. Provides good soil stabilization and erosion control in coastal sandy soils. High wildlife value for ground-nesting insects and small mammals within urban and suburban ecosystems.