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Stenotaphrum spp.
St. Augustine Grass
Tropical and subtropical coasts worldwide
Overview
Stenotaphrum is a genus of about seven warm-season grasses in the family Poaceae, found on tropical and subtropical coasts around the world. The plants are creeping, stoloniferous perennials that root at the nodes to form dense mats, with blunt-tipped, flattened blades 0.2-0.6 inch (4-15 mm) wide. The most cultivated species, S. secundatum, is grown widely as St. Augustine grass, a coarse warm-climate lawn turf. Flowering stems rise 4-12 inches (10-30 cm) above the mat and carry a flattened, spike-like inflorescence in which the spikelets are partly sunk into a thickened, corky axis. Stenotaphrum spreads vigorously by surface runners and tolerates salt spray, sandy soils, and coastal exposure, but is sensitive to hard frost and turns brown below about 55 F (13 C). It grows in full sun to moderate shade, more shade-tolerant than many warm-season turf grasses. Mat-forming growth can overrun bed edges and needs containment. Across the genus the grasses occupy dunes, coastal flats, and disturbed ground in frost-free to mild climates, and several are used for lawns, erosion control, and pasture.
Native Range
Stenotaphrum occurs on tropical and subtropical coasts worldwide, including the Americas, Africa, Asia, and Pacific and Indian Ocean islands. S. secundatum is native to coastal regions of the Gulf of Mexico, the Caribbean, and warm parts of Africa. Typical habitats are sandy shores, dunes, and coastal flats.Suggested Uses
Stenotaphrum is used as warm-season lawn turf, for coastal erosion control, and for ground stabilization on sandy and saline sites. Its salt tolerance suits seaside gardens and dune plantings. Some forms with variegated blades are grown as trailing container and groundcover plants.How to Identify
Appearance
Size & Dimensions
Height4" - 1'
Width/Spread2' - 10'
Bloom Information
Detailed Descriptions
Flower Description
green to tanFoliage Description
greenGrowing Conditions
Sun Requirements
Requires 4-12 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Stenotaphrum grows in full sun to moderate shade and tolerates a wide range of soils, including sandy and saline coastal ground. Water needs are medium; established mats withstand short drought but brown out in long dry spells. It performs in soil pH from about 5.0 to 8.5 and recovers quickly from wear by spreading runners. Growth slows and color fades below roughly 55 F (13 C), and hard frost damages or kills top growth, limiting it to USDA zones 8-11. The grass spreads aggressively and can invade borders and paths. Thatch builds up in vigorous stands and is managed by periodic dethatching.Pruning
Maintenance is by mowing rather than pruning, kept at 2.5-4 inches (6-10 cm) for lawn use. Runners that creep into beds and paths are trimmed back along edges. Thick thatch is removed periodically to keep the mat healthy.Container Growing
Suitable for container growing
Minimum container size: 2 gallons