St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, Subfamily Panicoideae, Tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common or 'Floratam' (typical of the coarse texture and purple-tinged stolons visible)
Hardiness Zones
USDA Hardiness Zones 8-11; poor cold tolerance; turns brown and dormant when temperatures drop below 55°F; does not survive ground freezes well.
About This Grass
A coarse-textured, low-growing grass that forms a thick, dense sod. It is deep green to blue-green and maintains color well into autumn. Unmowed, it can reach 12 inches; maintained, it creates a lush, spongy turf. Seed heads are inconspicuous spikes with seeds embedded in one side of a flattened rachis.
Blade Characteristics
Coarse width (8-10mm); flat shape with a distinct boat-shaped to rounded tip; dark green color; folded vernation; ligule is a fringe of short hairs; auricles are absent; collar region is broad and continuous.
Root System
Fibrous and relatively shallow to moderate depth; relies on thick stolons for lateral spread; high thatch-forming tendency; moderate establishment speed from sod or plugs.
Growing Information
Origin Region
Native to tropical and subtropical regions bordering the Atlantic (Gulf of Mexico, Caribbean, Africa)
Growth Habit
Stoloniferous; spreads aggressively via thick above-ground runners (stolons) to form a dense, carpet-like mat.
Sunlight & Water Needs
Partial sun to full sun (best shade tolerance of warm-season grasses); needs 4-6 hours minimum; high water requirements; moderate drought tolerance but wilts quickly without moisture; prefers well-drained, slightly acidic to neutral soils (pH 6.0-7.5).
Mowing & Maintenance
High maintenance; mowing height of 2.5 to 4.0 inches; frequency of every 5-7 days in peak season; requires 2-4 lbs of Nitrogen per 1000 sq ft annually; high dethatching needs.
Special Characteristics
Excellent shade tolerance for a warm-season grass; high salt tolerance (ideal for coastal areas); moderate wear tolerance but slow to recover from heavy traffic; susceptible to Large Patch (fungus) and Chinch Bugs.
Ecological Information
Introduced and naturalized in the Southern US; provides some cover for small soil-dwelling fauna; excellent for erosion control due to dense stolon matting; lacks invasive status in most managed landscapes but can encroach on flower beds.