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. Low cold tolerance and susceptible to freeze damage below 20°F. Goes dormant and turns straw-colored in cooler winter regions.
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Variety / Cultivar
'Floratam', a widely planted cultivar known for its coarse texture, blue-green color, and resistance to St. Augustine Decline (SAD) virus.
About This Grass
Forms a dense, lush, carpet-like turf with coarse-textured, broad blades. Light to dark blue-green in color. When unmowed, it can grow up to 6-12 inches tall, but it is typically maintained much lower. Produces flat, spike-like seed heads on terminal stalks.
Blade Characteristics
Blades are coarse, flat, typically 4-10 mm wide with rounded to obtuse tips. Vernation is folded in the bud. The ligule is a fringe of hairs, and auricles are absent. The collar region is continuous and broad.
Root System
Moderately deep fibrous root system combined with robust stolons. Tends to build up thatch if over-fertilized. Establishes quickly from sod, moderately fast from plugs.
Growing Information
Origin Region
Native to the coastal regions of the Gulf of Mexico, the Caribbean, and along the Mediterranean. Well-adapted to tropical and subtropical climates globally.
Growth Habit
Aggressively stoloniferous, spreading rapidly via above-ground runners (stolons) that root at the nodes, forming a thick, coarse sod.
Sunlight & Water Needs
Requires full sun to partial shade; it is the most shade-tolerant of the warm-season turfgrasses, needing at least 4 hours of direct sunlight. High water needs during active growth, with moderate drought tolerance by entering dormancy during severe dry spells.
Mowing & Maintenance
Ideal mowing height is 2.5 to 4 inches using a rotary mower. Requires medium to high maintenance, including regular irrigation, fertilization (2-4 lbs N per 1000 sq ft per year), and occasional dethatching.
Special Characteristics
Good salt tolerance making it popular for coastal areas. Moderate to low wear tolerance compared to Bermuda or Zoysia. Recovers well from stolons. Susceptible to chinch bugs, sod webworms, and large patch disease.
Ecological Information
Introduced and naturalized in many tropical and subtropical areas. Provides good erosion control on coastal soils and slopes. Offers habitat for various insects and ground-nesting wildlife. Often grown as a monoculture lawn.