St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
'Palmetto' or 'Floratam' (common commercially available cultivars known for shade or color retention)
Hardiness Zones
USDA Hardiness Zones 8-10. Low cold tolerance (susceptible to damage below freezing temperatures). Goes dormant and turns brown in cooler winters.
About This Grass
A coarse-textured, dense, low-growing turfgrass with flat, broad blades and blunt tips. It forms a thick carpet-like sod with bright green to blue-green coloring. Unmowed, it can grow up to 6-12 inches tall, but it is typically maintained much lower. Seed heads are flattened spikes.
Blade Characteristics
Blades are coarse (>4-10mm wide), flat, with blunt, rounded 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, often whitish or light green.
Root System
Moderately deep, fibrous root system working in conjunction with aggressive above-ground stolons. Forms a dense sod with a high tendency to produce thatch if over-fertilized. Establishes rapidly from plugs or sod.
Growing Information
Origin Region
Native to the Gulf of Mexico region, coastal areas of the southeastern United States, and the Caribbean. Thrives in tropical and subtropical climates.
Growth Habit
Stoloniferous, spreading aggressively via above-ground runners (stolons) with short internodes, forming a dense, coarse turf mat.
Sunlight & Water Needs
Requires full sun to partial shade (more shade tolerant than most warm-season grasses). High watering needs for optimal appearance; moderate drought tolerance by entering dormancy during severe dry spells. Prefers well-drained soils with a pH between 6.0 and 7.5.
Mowing & Maintenance
Ideal mowing height is 2.5 to 4 inches using a sharp rotary mower to avoid shredding the broad blades. Medium-high maintenance level requiring regular irrigation, moderate fertilization (2-4 lbs N per 1000 sq ft annually), and periodic dethatching.
Special Characteristics
Excellent shade tolerance compared to other warm-season turfgrasses, moderate salt tolerance (good for coastal areas), poor wear/traffic recovery due to coarse stoloniferous growth, and low tolerance to heavy compaction.
Ecological Information
Introduced and widely cultivated in warm coastal regions. Provides excellent soil stabilization and erosion control on coastal slopes and lawns. Offers limited wildlife food value but creates good micro-habitat within dense turf mats. Often grown as a monoculture lawn.