St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
'Palmetto' or 'Floratam' (common commercially available cultivars)
Hardiness Zones
USDA Hardiness Zones 8 through 10. Sensitive to hard frosts and extreme cold, going dormant in winter in the upper bounds of its range.
About This Grass
Forms a dense, coarse-textured turf with broad, flat leaf blades. Color is typically medium to dark green, turning straw-colored upon entering winter dormancy in cooler parts of its range. Unmowed height can reach several inches with flattened, upright seed stalks.
Blade Characteristics
Coarse texture with blades greater than 4mm in width. Flat, blunt-tipped (rounded) leaf blades. Rolled vernation in the bud, with a short membranous ligule fringed with hairs and absent auricles.
Root System
Moderate root depth with a robust fibrous root system and aggressive thick stolons. Forms a dense sod, tends to build up thatch moderately fast, and establishes quickly from sod.
Growing Information
Origin Region
Native to the Gulf of Mexico region, coastal areas, and tropical regions worldwide; well-adapted to the southern United States.
Growth Habit
Stoloniferous, spreading aggressively via above-ground runners (stolons) to form a thick, coarse turf mat.
Sunlight & Water Needs
Performs best in full sun but has the best shade tolerance among warm-season turfgrasses. Requires moderate to high moisture and regular watering; moderate drought tolerance by going into dormancy during prolonged dry spells.
Mowing & Maintenance
Ideal mowing height ranges from 2.5 to 4 inches. Requires regular weekly mowing during the growing season. Medium maintenance level with fertilization needs of 2 to 4 lbs N per 1,000 sq ft annually.
Special Characteristics
Good shade tolerance and salt tolerance, making it popular in coastal regions. Moderate traffic tolerance; recovers well from damage via stolons but susceptible to chinch bugs and large patch disease.
Ecological Information
Introduced and widely cultivated in warm coastal areas. Provides good erosion control on sandy coastal soils and stabilizes shorelines, though it can outcompete native vegetation if allowed to escape into natural areas.