St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae, tribe Panicae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
'Floratam' (most common wide-bladed cultivar with good drought and insect resistance)
Hardiness Zones
Thrives in USDA Hardiness Zones 8 through 10. Poor cold tolerance; damaged by prolonged freezes below 20°F. Goes dormant and turns brown in winter in cooler parts of its range.
About This Grass
A coarse-textured, low-growing warm-season turfgrass forming a dense, carpet-like sward. Typically maintained between 2.5 and 4 inches in height. Color is vibrant blue-green to dark green during the growing season, turning brown or straw-colored during winter dormancy.
Blade Characteristics
Blades are coarse (>4mm wide, typically 6-10mm), flat, with blunt, rounded tips. Vernation is folded in the bud. Ligule is a fringe of hairs. Auricles are absent. Texture is soft compared to other warm-season grasses.
Root System
Moderately deep fibrous root system originating from nodes along the stolons. Spreads rapidly via stolons rather than underground rhizomes. Moderate thatch-forming tendency.
Growing Information
Origin Region
Native to tropical and subtropical coastal regions around the Gulf of Mexico, Caribbean, and West Africa. Widely cultivated in the southern United States and tropical regions worldwide.
Growth Habit
Stoloniferous (spreading aggressively via above-ground runners called stolons) forming a coarse, dense turf mat.
Sunlight & Water Needs
Requires full sun to moderate shade (most shade tolerant of all warm-season grasses, requiring at least 4 hours of direct sun). High water needs during establishment and dry periods; moderate drought tolerance with some dormancy. Prefers well-draining soils with a pH of 6.0 to 7.5.
Mowing & Maintenance
Mow at 2.5 to 4 inches high using a sharp rotary mower. Fertilization needs are moderate to high (2 to 5 lbs N per 1000 sq ft annually). Requires periodic dethatching and core aeration. Maintenance level is moderate.
Special Characteristics
Low to moderate wear/traffic tolerance due to fleshy stolons. Susceptible to chinch bugs, sod webworms, and diseases like take-all root rot and brown patch. Good salt tolerance, making it popular in coastal areas.
Ecological Information
Introduced species in many non-native warm regions. Provides moderate ground cover and erosion control, especially in sandy coastal soils. Low wildlife value compared to native prairie grasses. Often planted as a monoculture turf.