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-like variety (highly coarse texture and long internodes)
Hardiness Zones
USDA Hardiness Zones 8-11; poor cold tolerance; enters dormancy and turns brown when temperatures drop below 50°F regularly
About This Grass
A coarse-textured, low-growing grass that forms a thick sod. It has a distinctive blue-green to dark green color, thick fleshy stolons, and short, blunt leaves. Seed heads are inconspicuous spikes with seeds embedded in a thickened rachis.
Blade Characteristics
Blade width: Coarse (>4mm, often 8-10mm); Shape: Flat; Tip: Distinctly rounded or boat-shaped; Color: Medium to dark green with a blueish tint; Vernation: Folded in the bud; Ligule: A fringe of short hairs; Auricles: Absent; Collar: Continuous and usually constricted
Root System
Moderately deep fibrous roots originating from stolon nodes; slow to moderate establishment from sprigs or plugs; high thatch-forming tendency; forms a very dense sod when healthy
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, creeping above-ground runners called stolons); forms a dense, carpet-like mat
Sunlight & Water Needs
Full sun to partial shade (one of the most shade-tolerant warm-season grasses); needs at least 4-6 hours of sun; high water requirement; moderate drought tolerance but wilts quickly without moisture
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; High maintenance due to water and pest needs
Special Characteristics
Excellent shade tolerance compared to other warm-season grasses; high salt tolerance (ideal for coastal areas); poor wear tolerance due to succulent stolons; susceptible to Chinch Bugs and Large Patch disease
Ecological Information
Native to coastal areas; provides soil stabilization in sandy soils; non-invasive in most upland environments but can dominate local garden beds; often used as a monoculture turf