St. Augustine Grass
Stenotaphrum secundatum · Warm-season, Perennial, C4 grass
Grass Family
Poaceae, subfamily Panicoideae, tribe Paniceae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Floratam (widely planted cultivar known for its coarser texture and virus resistance)
Hardiness Zones
Thrives in USDA Hardiness Zones 8 through 10. Low cold tolerance compared to other warm-season grasses; susceptible to freeze damage below 20 degrees Fahrenheit.
About This Grass
St. Augustine grass is a coarse-textured, dense, warm-season turfgrass with a bright to dark green color. When unmowed, it can grow up to 6 to 12 inches tall, but it is typically maintained at a height of 2.5 to 4 inches. It goes into winter dormancy and turns brown in cooler regions.
Blade Characteristics
Blades are coarse, wider than 4mm (typically 5-10mm wide), flat, with rounded tips. Vernation is folded in the bud. The ligule is a fringe of hairs, and auricles are absent. The collar is continuous and broad.
Root System
Moderately deep fibrous root system originating from nodes along the stolons. Forms a thick layer of thatch quickly if over-fertilized. Establishes rapidly from sod or plugs.
Growing Information
Origin Region
Native to the Gulf of Mexico region, coastal areas of the Americas, and West Africa. Well-adapted to tropical and subtropical climates.
Growth Habit
Aggressively stoloniferous, forming a dense, coarse-textured mat by spreading via above-ground runners (stolons).
Sunlight & Water Needs
Requires full sun to moderate shade (more shade-tolerant than most warm-season grasses). Needs regular watering (about 1 inch of water per week) and has moderate drought tolerance, entering dormancy during severe dry spells.
Mowing & Maintenance
Ideal mowing height is 2.5 to 4 inches using a sharp rotary mower to prevent tearing the coarse blades. Requires medium to high maintenance, including regular fertilization (2 to 4 lbs N per 1000 sq ft per year) and occasional dethatching.
Special Characteristics
Excellent salt tolerance making it popular in coastal areas. Moderate traffic and wear tolerance with good recuperative ability via stolons. Susceptible to chinch bugs and large patch disease.
Ecological Information
Introduced/cultivated across subtropical regions worldwide. Provides good soil stabilization and erosion control in sandy coastal soils. Minimal invasive tendency outside of cultivated landscapes.