St. Augustine Grass
Stenotaphrum secundatum · Warm-season perennial, C4 carbon fixation
Grass Family
Poaceae, Subfamily Panicoideae, Tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common or Floratam-type (likely non-dwarf variety based on coarse texture)
Hardiness Zones
USDA Zones 8-11; poor cold tolerance; enters dormancy and turns brown when soil temperatures drop below 55°F; prone to winter kill in Zone 7 and above.
About This Grass
A coarse-textured, low-growing grass with a dense, carpet-like appearance. It has a medium to dark green color and produces thick, succulent stolons. When unmowed, it can reach 6-12 inches; seed heads are inconspicuous, spike-like racemes embedded in a thickened rachis.
Blade Characteristics
Coarse width (8-10mm); flat shape with a distinctively blunt, rounded (boat-shaped) tip; foliage is medium green; vernation is folded; ligule is a short fringe of hairs; auricles are absent; collar is continuous and constricted.
Root System
Fibrous and moderately deep, primarily emerging from stolon nodes; high thatch-forming tendency; slows to establish from seed (usually sodded or plugged); forms a dense, competitive sod.
Growing Information
Origin Region
Native to coastal regions of the Gulf of Mexico, Caribbean, and Mediterranean; well-adapted to humid subtropical climates
Growth Habit
Stoloniferous (spreads via thick, creeping above-ground runners); heavy mat-forming
Sunlight & Water Needs
Partial shade to Full Sun (one of the most shade-tolerant warm-season grasses); requires at least 4-6 hours of sun; high water needs; moderate drought tolerance but wilts quickly without moisture; prefers well-drained, slightly acidic to neutral soils.
Mowing & Maintenance
Ideal height 3.0-4.0 inches; weekly frequency; fertilization 2-4 lbs N per 1000 sq ft per year; high dethatching needs; high maintenance level due to water and pest monitoring requirements.
Special Characteristics
Excellent shade tolerance for a warm-season grass; high salt tolerance (good for coastal areas); moderate wear tolerance but slow to recover; susceptible to Chinch Bugs and Large Patch (Brown Patch) disease.
Ecological Information
Introduced/Naturalized in North America; provides soil stabilization for coastal dunes; low wildlife value; can be invasive in sensitive wetland margins; usually grown as a monostand rather than in mixes.