St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4
Grass Family
Poaceae, Subfamily Panicoideae, Tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common or Floratam-type (likely standard residential cultivar)
Hardiness Zones
USDA Zones 8-11. Excellent heat tolerance; poor cold tolerance. Enters dormancy and turns brown when soil temperatures drop below 55°F.
About This Grass
A coarse-textured, low-growing grass with a bright to medium green color. It maintains a very dense sod when healthy and features a characteristic creeping growth habit. In unmaintained states, it can reach 6-12 inches, but it is typically kept short. Seed heads are spike-like racemes with seeds embedded in a thickened rachis.
Blade Characteristics
Coarse width (>4mm), blades are typically flat with a distinctive rounded/blunt boat-shaped tip. Color ranges from lime green to blue-green. Vernation is folded in the bud. Ligule is a fringe of short hairs; auricles are absent; the collar is continuous and somewhat constricted.
Root System
Moderately deep fibrous root system originating from stolon nodes. It has a high thatch-forming tendency and establishes relatively quickly from sod or plugs but not from seed.
Growing Information
Origin Region
Native to coastal regions of the Gulf of Mexico, Caribbean, and Western Africa; highly adapted to humid subtropical climates.
Growth Habit
Stoloniferous; spreads aggressively via thick above-ground runners (stolons) to form a dense, carpet-like mat.
Sunlight & Water Needs
Partial Shade to Full Sun; one of the most shade-tolerant warm-season grasses. Requires moderate to high water (approx. 1 inch per week). Prefers well-drained, sandy or loamy soils with pH 6.0-7.5.
Mowing & Maintenance
Mowing height: 2.5 to 4.0 inches. Frequency: weekly during growing season. Fertilization: 2-4 lbs N per 1000 sq ft annually. Requires periodic dethatching and core aeration. Maintenance level: Medium-High.
Special Characteristics
Excellent shade tolerance for a warm-season grass; good salt tolerance (ideal for coastal areas); moderate wear tolerance; highly susceptible to Chinch bugs and Gray Leaf Spot disease.
Ecological Information
Introduced/Naturalized in many tropical regions. Provides excellent soil stabilization and erosion control. Low wildlife food value but provides cover for small invertebrates. Often grows alongside White Clover (Trifolium repens) as seen in this specimen.