St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, Subfamily Panicoideae, Tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common variant (likely 'Floratam' or 'Palmetto' based on blade width and growth pattern)
Hardiness Zones
USDA Zones 8-11. Poor cold tolerance; enters dormancy and turns brown when temperatures drop below 55°F consistently.
About This Grass
A coarse-textured, low-growing turfgrass that forms a dense, carpet-like mat. It features wide, blunt blades and a vibrant medium-to-dark green color. When unmowed, it can reach 6-12 inches; seed heads are inconspicuous spikes embedded in a flattened rachis.
Blade Characteristics
Coarse width (8-10mm), flat shape with a distinct boat-shaped/rounded tip. Color is bright green to deep blue-green. Vernation is folded in the bud. It lacks auricles, and the ligule is a short fringe of hairs.
Root System
Moderately deep fibrous root system emerging from stolon nodes. Low thatch tendency compared to Bermuda, but can build up if over-fertilized. Establishment speed is moderate via sod or plugs.
Growing Information
Origin Region
Native to the Gulf of Mexico region, West Indies, and West Africa. Thrives in tropical and subtropical coastal regions.
Growth Habit
Stoloniferous; spreads rapidly via thick, creeping above-ground runners (stolons). It does not produce rhizomes.
Sunlight & Water Needs
Partial Sun to Full Sun; one of the most shade-tolerant warm-season grasses (needs at least 4-5 hours). Moderate to high water needs; poor drought tolerance compared to Bermuda.
Mowing & Maintenance
Ideal height: 2.5 to 4.0 inches. Mowing frequency: 7-10 days. Fertilization: 2-4 lbs Nitrogen per 1000 sq ft per year. Low to Medium maintenance level.
Special Characteristics
Excellent shade tolerance for a warm-season grass, high salt tolerance (ideal for coastal areas), and good ability to crowd out weeds due to dense stolon mat. Poor wear tolerance.
Ecological Information
Native to coastal regions. Provides soil stabilization in sandy areas. Not considered invasive in its native range but can dominate local niche ecosystems. Often paired with Large Crabgrass as a weed competitor.