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 common coastal use and blade width
Hardiness Zones
USDA Zones 8-11; poor cold tolerance; enters dormancy and turns brown when soil temperatures drop below 55°F.
About This Grass
A coarse-textured, low-growing grass that forms a thick, spongy sod. It features a medium to dark green color and remains green longer into the fall than other warm-season grasses. Seed heads are inconspicuous spikes with seeds embedded in one side of a flattened rachis.
Blade Characteristics
Coarse blade width (>4mm), folded vernation, rounded or blunt-shaped tips. Ligule is a fringe of short hairs; auricles are absent. The collar is constricted and smooth.
Root System
Moderately deep fibrous root system originating from stolon nodes; slow to establish from seed (primarily sod/plugs); low to moderate thatch tendency; high wear recovery through lateral growth.
Growing Information
Origin Region
Native to coastal regions of the Gulf of Mexico, Caribbean, and Mediterranean; adapted to tropical and subtropical climates
Growth Habit
Stoloniferous; spreads via thick, above-ground runners (stolons) to form a dense, carpet-like mat
Sunlight & Water Needs
Partial Sun to Full Sun (one of the most shade-tolerant warm-season grasses); requires at least 4-6 hours of sunlight; high water needs; moderate drought tolerance; prefers well-drained soil with pH 6.0-7.5.
Mowing & Maintenance
Ideal height 2.5 to 4.0 inches; weekly frequency; 2-4 lbs Nitrogen per 1000 sq ft per year; medium maintenance level; susceptible to Chinch bugs.
Special Characteristics
Excellent shade tolerance for a warm-season grass; high salt tolerance (ideal for coastal lawns); moderate traffic tolerance; prone to Gray Leaf Spot and Large Patch disease.
Ecological Information
Introduced/Naturalized in the US; provides soil stabilization for coastal sandy soils; non-invasive in most upland ecosystems but can spread in moist riparian zones.