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' (most common widespread commercial cultivar with coarse, blue-green blades)
Hardiness Zones
Thrives in USDA Hardiness Zones 8 through 10; sensitive to hard frosts and prolonged freezing temperatures, entering winter dormancy where temperatures drop consistently below 50 degrees Fahrenheit
About This Grass
Forms a dense, coarse-textured turf with flat, broad blades and blunt tips; vibrant medium to dark green color that goes dormant (turns straw-colored) in winter in colder regions; typically maintained at 2.5 to 4 inches height
Blade Characteristics
Coarse texture with blade width generally 4-10 mm; flat shape with rounded, blunt tips; folded vernation in the bud; light to medium green or blue-green color; smooth texture with prominent ligule consisting of a fringe of hairs and absent auricles
Root System
Moderately deep fibrous root system originating from nodes along the thick stolons; moderate to high thatch-forming tendency; establishes quickly from sod or plugs; forms a thick, spongy sod
Growing Information
Origin Region
Native to tropical and subtropical regions along the Gulf of Mexico, the Caribbean, and coastal areas worldwide; thrives in humid coastal climates
Growth Habit
Stoloniferous, spreading aggressively via thick above-ground runners (stolons) and forming 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 (approximately 1 inch per week) and has moderate to good drought tolerance by entering dormancy during dry periods; prefers well-draining soils with a pH between 5.5 and 7.5
Mowing & Maintenance
Ideal mowing height ranges from 2.5 to 4 inches using a sharp rotary mower; requires medium-high maintenance including regular fertilization (2 to 4 lbs N per 1000 sq ft annually), occasional dethatching, and consistent watering
Special Characteristics
Excellent shade tolerance compared to other warm-season grasses, moderate to low traffic/wear tolerance due to coarse stolon structure, susceptible to chinch bugs and take-all root rot, moderate salt tolerance making it popular in coastal regions
Ecological Information
Introduced and naturalized widely across warm coastal regions; provides limited wildlife habitat compared to native prairie grasses; excellent for soil stabilization and erosion control in coastal areas; rarely used in seed mixes as it is almost exclusively established via sod, plugs, or sprigs