Sabal causiarum
 
Common Names Puerto Rican Hat Palm, Puerto Rico Palmetto
 
Zones 8b–11
 
A massive, solitary fan palm native to Puerto Rico and the Greater Antilles, Sabal causiarum is known for its stout trunk, smooth gray stem, and broad, costapalmate leaves. Historically used in hat-making and thatch, this species is now prized for its architectural presence in large landscapes and restoration projects. It tolerates drought, salt, and poor soils, making it ideal for coastal and xeric settings.
 
Key Features
Growth Habit: Solitary; upright; tillering with saxophone-style root heel
Height: 30–50 ft (9–15 m); trunk diameter 14–28 in (35–70 cm)
Trunk: Smooth gray; leaf bases shed early; close ring scars
Leaves: Costapalmate; 20–30 leaves per crown; 60–120 rigid segments per leaf; up to 6 ft (1.8 m) wide
Inflorescence: Bisexual flowers; pendulous, branched to 3 orders; fruit black, globose, 0.3–0.4 in (7–11 mm) diameter
Ecology: Native to Puerto Rico, Hispaniola, and Virgin Islands; found on coastal plains and sandy soils up to 1,000 ft (300 m) elevation
 
Growing Conditions
Light: Full sun
Watering: Low once established; drought tolerant
Soil: Prefers well-drained sandy or loamy soils; tolerates poor substrates
Temperature: Hardy to ~15°F (–9°C)
Humidity: Tolerant of dry air
Propagation: By seed; slow germination
Tolerance: Salt, drought, poor soils, urban conditions
 
Landscape Use Best suited for large-scale landscapes, coastal restoration, and public gardens. Its massive trunk and broad crown make it a focal specimen. Pairs well with Copernicia baileyana, Coccothrinax crinita, and Acoelorrhaphe wrightii.