St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, Subfamily Panicoideae, Tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Likely 'Floratam' or 'Palmetto' based on blade width and coarse texture
Hardiness Zones
USDA Hardiness Zones 8-10. Poor cold tolerance; goes dormant and turns brown after the first hard frost. Cannot survive sustained freezing temperatures.
About This Grass
A coarse-textured, low-growing turfgrass that forms a thick, carpet-like sod. It is deep green to blue-green in color and retains its color well into the fall. Seed heads are inconspicuous, appearing as small spikes on a flattened stem (rachis).
Blade Characteristics
Coarse blade width (>4mm), flat shape with a distinctively rounded or 'boat-shaped' tip. Vernation is folded in the bud. Light to medium green. It has a short, fringe-like hairy ligule and no auricles. The collar is continuous and narrow.
Root System
Fibrous and moderately deep, primarily supported by stolons. It has a high thatch-forming tendency and moderate establishment speed from sod or plugs. Forms a very dense sod that competes well against weeds.
Growing Information
Origin Region
Native to the coastal areas of the Gulf of Mexico, the Mediterranean, and West Africa; adapted to humid subtropical and tropical climates
Growth Habit
Stoloniferous; spreads via aggressive above-ground horizontal stems (stolons) to form a dense, thick mat
Sunlight & Water Needs
Partial sun to full sun; one of the most shade-tolerant warm-season grasses. Needs at least 4-5 hours of direct sun. High water requirements; poor drought tolerance compared to Bermuda, prefers moist, well-drained soils with pH 5.0-8.5.
Mowing & Maintenance
Recommended mowing height is 2.5 to 4.0 inches. Frequency is weekly during peak growth. Fertilization: 2-4 lbs N per 1000 sq ft annually. High maintenance level due to water and pest monitoring needs.
Special Characteristics
Excellent shade tolerance for a warm-season grass, high salt tolerance (ideal for coastal areas), and moderate traffic tolerance. Susceptible to Large Patch (fungus) and Chinch Bugs.
Ecological Information
Introduced and naturalized in many regions. Excellent for soil stabilization and erosion control in coastal sandy soils. Not considered invasive in managed landscapes but can crowd out native species in sensitive wetland margins.