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 moderate shade tolerance and coarse, blue-green texture
Hardiness Zones
USDA Hardiness Zones 8 through 10; excellent heat tolerance; poor cold tolerance (susceptible to frost damage and winter dormancy discoloration); not suitable for the transition zone further north
About This Grass
Forms a lush, dense, carpet-like turf with coarse, flat blades. Color ranges from medium to dark blue-green. Can grow rapidly during warm summer months, reaching several inches in height if unmanaged. Produces flattened spike-like seed heads.
Blade Characteristics
Blades are coarse (>4mm wide), flat, with blunt or rounded tips, folded in the bud (vernation), smooth texture, prominent parallel veins, membranous ligule with a fringe of hairs, and absent or very small auricles
Root System
Moderately deep fibrous root system originating from nodes along the thick stolons; moderate establishment speed; forms a spongy thatch layer quickly if over-fertilized
Growing Information
Origin Region
Native to tropical and subtropical regions globally along coasts; widely cultivated in the Southern United States and coastal regions worldwide
Growth Habit
Stoloniferous, spreading aggressively via thick above-ground runners (stolons) to form a dense, coarse-textured sod
Sunlight & Water Needs
Requires full sun to partial shade (more shade tolerant than many warm-season grasses); needs regular moisture and moderate watering; moderate to good drought tolerance by entering dormancy during extreme dry spells; prefers well-draining soils with a pH of 5.5 to 7.0
Mowing & Maintenance
Mow at 2.5 to 3.5 inches high; frequency is weekly during the growing season; fertilization requires 2 to 4 lbs N per 1000 sq ft per year; periodic dethatching is needed due to rapid stolon production; maintenance level is medium to high
Special Characteristics
Low to moderate wear/traffic tolerance due to fleshy stolons; good salt tolerance making it ideal for coastal lawns; prone to certain fungal diseases like Take-All Root Rot and chinch bug infestations; slow recovery from heavy damage
Ecological Information
Introduced and naturalized in many tropical and subtropical areas; provides good erosion control on coastal sandy soils; forms dense monocultures that naturally crowd out weeds; provides minimal wildlife value compared to native prairie grasses