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 wide-bladed cultivar with good drought and insect resistance)
Hardiness Zones
USDA Hardiness Zones 8-10. Sensitive to freezing temperatures and will go dormant and turn brown with the first heavy frost. Poor cold tolerance compared to other warm-season grasses.
About This Grass
Forms a thick, carpet-like turf with coarse texture. Color is typically blue-green to dark green. Unmowed height can reach 6-12 inches, but it is typically maintained between 2.5 and 4 inches. Produces flat, upright seed heads (spikes) on flattened stems at maturity.
Blade Characteristics
Coarse-textured blades (>4mm wide, typically 6-10mm), flat, with rounded to somewhat blunt tips. Folded vernation 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 originating from nodes along the stolons. Establishes relatively quickly from sod or plugs. Prone to thatch accumulation under high fertilization and watering.
Growing Information
Origin Region
Native to tropical and subtropical coastal regions of the Americas and West Africa; widely cultivated across the Southern United States, Gulf Coast, Florida, and parts of California and Hawaii.
Growth Habit
Stoloniferous and rhizomatous, spreading aggressively via above-ground runners (stolons) to form a dense, coarse-textured sod.
Sunlight & Water Needs
Requires full sun to partial shade (more shade-tolerant than most warm-season grasses, needing at least 4 hours of direct sun). High watering needs for optimal appearance; moderate drought tolerance as it enters dormancy during severe dry spells.
Mowing & Maintenance
Mow at 2.5 to 4 inches every 7-10 days during the growing season. Fertilization requires 2-4 lbs N per 1000 sq ft annually. Medium to high maintenance level, requiring regular irrigation, weeding, and occasional dethatching.
Special Characteristics
Moderate traffic/wear tolerance (not as durable as Bermuda or Zoysia), poor to moderate cold tolerance, good shade tolerance for a warm-season grass, susceptible to chinch bugs, sod webworms, and Take-All Root Rot.
Ecological Information
Introduced and naturalized in many tropical/subtropical regions. Provides good soil stabilization and erosion control on coastal sites. Serves as a wildlife habitat and food source for various insects and small mammals, though often managed intensively as a monoculture lawn.