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' (common, coarse-textured cultivar with good drought and disease resistance)
Hardiness Zones
USDA Hardiness Zones 8 through 10. Highly sensitive to freezing temperatures and enters winter dormancy in cooler parts of its range.
About This Grass
St. Augustine grass is a coarse-textured, low-growing turfgrass that forms a dense carpet-like lawn. It features a bright blue-green to dark green color in the growing season. Unmowed, it can reach heights of 6 to 12 inches, but when maintained, it is typically kept around 2.5 to 4 inches tall. Seed heads are produced on flattened spikes.
Blade Characteristics
Blades are broad (coarse, typically 4-10 mm wide), flat, with rounded tips. Vernation is folded in the bud. The ligule is a fringe of hairs, and auricles are absent. The collar region is continuous.
Root System
Moderately deep fibrous root system originating from nodes along the stolons. Establishes relatively quickly from sod, forms a dense sod layer, but has a moderate tendency to produce thatch if over-fertilized.
Growing Information
Origin Region
Native to tropical and subtropical regions along the Gulf of Mexico, the Caribbean, and coastal areas worldwide; thrives best in humid tropical and subtropical climates.
Growth Habit
Stoloniferous, spreading aggressively via thick above-ground runners (stolons) to form a dense, coarse turf mat.
Sunlight & Water Needs
Requires full sun to partial shade (more shade-tolerant than most warm-season grasses). Needs regular watering (1 inch per week) and has moderate drought tolerance, entering dormancy during prolonged dry spells.
Mowing & Maintenance
Ideal mowing height is 2.5 to 4 inches using a rotary mower with sharp blades to prevent tearing. Medium maintenance level requiring regular fertilization, occasional dethatching, and monitoring for pests like chinch bugs.
Special Characteristics
Good shade tolerance for a warm-season grass, moderate salt tolerance (ideal for coastal regions), but poor cold tolerance and low traffic wear tolerance compared to Bermuda grass.
Ecological Information
Introduced and naturalized in many coastal regions. Provides ground cover and soil stabilization against erosion, offers limited wildlife habitat, and can form dense monocultures that crowd out weeds.