St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Lawn / Turf Grass
Variety / Cultivar
Common or Floratam-type (likely a base cultivar given the coarse texture and broad blades)
Hardiness Zones
USDA Zones 8-11. Poor cold tolerance; turns brown and dormant when temperatures drop below 50°F (10°C). High heat and humidity tolerance.
About This Grass
A coarse-textured, low-growing grass with a vibrant blue-green to dark green color. It forms a thick sod through aggressive surface stolons. Unmowed, it can reach 6-12 inches; maintained, it creates a lush, carpet-like surface. Seed heads are spike-like racemes with seeds embedded in a thick rachis.
Blade Characteristics
Broad blades (8-10mm), rounded or blunt tips, coarse texture. Vernation is folded. Ligule is a fringe of short hairs; auricles are absent. Distinctive constricted collar region.
Root System
Extensive fibrous roots originating from stolon nodes; moderate depth; high thatch-forming tendency; slow to moderate establishment from plugs or sod (rarely grown from seed).
Growing Information
Origin Region
Coastal regions of the Gulf of Mexico, Caribbean, and Africa; well-adapted to tropical and subtropical climates
Growth Habit
Stoloniferous (spreading above ground via thick, fleshy runners), forming a dense, coarse mat
Sunlight & Water Needs
Prefers full sun but has excellent shade tolerance (best among warm-season grasses). Requires 4-6 hours of sun. Needs regular watering; moderate drought tolerance but will wilt and go dormant without irrigation in sandy soils.
Mowing & Maintenance
Recommended height of 2.5 to 4.0 inches. Mowing frequency is weekly during the growing season. High nitrogen demand (3-6 lbs N per 1000 sq ft annually). Requires periodic dethatching and aeration.
Special Characteristics
Excellent shade tolerance and high salt tolerance (good for coastal areas). Poor wear tolerance (sensitive to heavy foot traffic). Susceptible to Chinch Bugs and Gray Leaf Spot.
Ecological Information
Introduced/Naturalized in the US. Provides excellent soil stabilization. Low wildlife food value but provides cover for small insects and reptiles. Often used as a mono-stand rather than in blends; compatible with some Clover or Dichondra in non-traditional lawns.