St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
'Palmetto' or 'Floratam', known for broad blades and coarse texture
Hardiness Zones
Thrives in USDA Hardiness Zones 8-10. Has poor cold tolerance and goes dormant with a brown color when temperatures drop below freezing.
About This Grass
Forms a dense, coarse-textured turf with blue-green to deep green blades. Grows relatively low to the ground and spreads rapidly through thick above-ground stolons. Unmowed heights can reach 6-12 inches, but typically maintained lower. Produces flat, spike-like seed heads.
Blade Characteristics
Blades are wide (typically 4-10mm, coarse), flat, with rounded tips, folded vernation in the bud, and a smooth, hairless texture. The collar region has a membranous ligule with a fringe of hairs, and auricles are absent.
Root System
Moderately deep fibrous root system with thick, aggressive stolons rooting at the nodes. Forms a dense sod with a moderate to high thatch tendency and fast establishment from plugs or sod.
Growing Information
Origin Region
Native to tropical and subtropical coastal regions around the Gulf of Mexico, Caribbean, and parts of Africa; widely cultivated throughout the southern United States.
Growth Habit
Stoloniferous, spreading rapidly via thick surface runners (stolons) to form a dense, coarse-textured mat.
Sunlight & Water Needs
Performs best in full sun, but is the most shade-tolerant of the warm-season turfgrasses. Requires moderate to high moisture and regular irrigation during dry periods. Low to moderate drought tolerance; enters dormancy or wilts quickly under severe drought.
Mowing & Maintenance
Ideal mowing height ranges from 2.5 to 4 inches. Requires frequent mowing during the active growing season. Fertilization needs are moderate to high (2-4 lbs N per 1000 sq ft per year). Regular dethatching and occasional aeration are beneficial; high maintenance level.
Special Characteristics
Low to moderate traffic/wear tolerance (stolons can be easily crushed under heavy use). Susceptible to chinch bugs, take-all root rot, and brown patch. Poor salt tolerance compared to seashore paspalum, but moderate among turf grasses. Excellent shade tolerance for a warm-season grass.
Ecological Information
Introduced in many parts of its cultivated range; provides low wildlife food value compared to native grasses but offers good soil stabilization and erosion control in coastal sandy soils due to its dense mat-forming stolons.