St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
'Floratam' (a widely used cultivar known for its coarse texture and blue-green color)
Hardiness Zones
Thrives in USDA Hardiness Zones 8 through 10. Excellent heat tolerance, but poor cold tolerance (susceptible to frost damage and enters winter dormancy with straw-like color in cooler parts of its range).
About This Grass
Forms a thick, carpet-like turf with coarse, flat blades and a vibrant blue-green to dark green color. It typically grows to a height of 2 to 3 inches when maintained as a lawn, but can reach over 6 inches if left unmowed. Produces a flat, spike-like seed head at maturity.
Blade Characteristics
Blades are coarse (typically 4-10mm wide), flat, with rounded or blunt 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
Moderate depth with a strong fibrous root system anchored by vigorous above-ground stolons. Forms a dense sod, though it has a higher tendency to produce thatch compared to some other warm-season grasses. Establishes relatively quickly from sod or plugs.
Growing Information
Origin Region
Native to the Gulf of Mexico region, coastal areas of the southeastern United States, and the Caribbean; well-adapted to tropical and subtropical climates globally.
Growth Habit
Stoloniferous, spreading rapidly via thick surface runners (stolons) to form a coarse, dense turf mat.
Sunlight & Water Needs
Requires full sun to partial shade (more shade-tolerant than most warm-season grasses, needing at least 4 hours of direct sunlight). High water needs during establishment and active growth; moderate drought tolerance as it enters dormancy during severe dry spells. Prefers moist, well-draining soils with a pH between 6.0 and 7.5.
Mowing & Maintenance
Ideal mowing height is 2.5 to 3.5 inches. Mowed weekly during the growing season. Fertilization requires 2 to 4 lbs N per 1000 sq ft annually. High maintenance level due to susceptibility to pests (such as chinch bugs) and thatch management.
Special Characteristics
Good salt tolerance, making it popular in coastal regions. Excellent shade tolerance relative to other warm-season turfgrasses. Moderate traffic and wear tolerance, but slow to recover from severe damage due to its stoloniferous-only spreading nature (lacks rhizomes).
Ecological Information
Introduced and naturalized in many tropical regions worldwide. Provides good soil stabilization and erosion control in coastal sandy soils. Serves as a habitat for various insects and small ground-dwelling wildlife in suburban and coastal ecosystems.