St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Floratam (or similar wide-blade cultivar)
Hardiness Zones
USDA Hardiness Zones 8-11. Sensitive to cold; enters winter dormancy and turns brown when soil temperatures drop below 55°F.
About This Grass
A coarse-textured, low-growing grass forming a thick, dense carpet. It features wide blades and a deep blue-green to medium green color. Seed heads are inconspicuous, appearing as short, thick spikes (racemes) with seeds embedded on one side.
Blade Characteristics
Coarse width (4-10mm), flat shape with rounded or boat-shaped tips. Vernation is folded in the bud. Ligule is a fringe of short hairs, and auricles are absent. The collar region is continuous and constricted.
Root System
Moderately deep fibrous roots originating from stolon nodes; high thatch-forming tendency; moderate establishment speed from sod or plugs.
Growing Information
Origin Region
Coastal regions of the Gulf of Mexico, Caribbean, and West Africa; adapted to tropical and subtropical climates
Growth Habit
Stoloniferous (spreading via thick, above-ground runners)
Sunlight & Water Needs
Full sun to partial shade; requires at least 4-5 hours of direct sun. High water needs; moderate drought tolerance but susceptible to wilting during prolonged dry periods. Prefers slightly acidic to neutral pH (5.0-8.5).
Mowing & Maintenance
Mowing height of 3.0 to 4.0 inches; weekly frequency during peak growth. Fertilization: 2-4 lbs N per 1000 sq ft per year. High maintenance level due to water and pest requirements.
Special Characteristics
Excellent shade tolerance compared to other warm-season grasses; high salt tolerance (ideal for coastal areas); poor wear tolerance due to thick, succulent stolons; susceptible to Chinch Bugs and Large Patch disease.
Ecological Information
Introduced/Naturalized in North America; provides soil stabilization in sandy coastal soils; low wildlife value; non-invasive in most managed landscapes but can crowd out native species in sensitive coastal dunes.