This spectacular grove of Puerto Rican hat palms can be seen at Miami's Fairchild Tropical Garden.
One of the most striking Sabal species is Sabal causiarum, the Puerto Rican hat palm. This palm is distinguished from other Sabals by its massive smooth gray trunk which can grow up to 4 ft (1.2 m) in diameter! Most Sabals retain their old leaf bases on the trunk, creating a textured crisscross or "cabbage leaf" pattern instead of a smooth trunk.
The leaves of Puerto Rican hat palm are large, usually about 6 ft (1.8 m) long and just as wide. They are costapalmate, which means the petiole, or leaf stem, extends into the leaf. The leaves are deep green in color and are deeply divided to about half their length into several segments which may droop at the ends.
The Puerto Rican hat palm forms a dense canopy of about 40 leaves. As the older leaves droop to 45-90 degree angles from the trunk, they turn brown, die and fall off. Many other Sabal species, like Florida's native cabbage palm (Sabal palmetto) tend to retain a 'hula skirt' of dead leaves about its trunk.
Sabal causiarum, which can grow up to 50 ft (15.2 m) in height, produces long flower stalks which hang out over the canopy. The numerous small flowers are white to cream in color. The round fruits are about 0.5 in (1.3 cm) in diameter and usually brown or black.
Location Sabal causiarum, the Puerto Rican hat palm, is native to Puerto Rico, the island of Hispaniola (Dominican Republic and Haiti) and adjacent Caribbean islands.
These are Jack's young Puerto Rican hat palms surviving a Zone 8 winter in Tallahassee, Florida. They were planted as seedlings ten years prior to this photo taken in early 2000.
These are the same palms eight years later. The largest is about 22 ft (6.7 m) in height. Once their trunks grew to maximum diameter at the ground the thick trunks begin to elongate (they have a couple feet of trunk now. These palms are slow growers! It will be a while before they look like the massively spectacular specimens at the Fairchild Tropical Garden.
Adaptable to different soil types but prefers very well drained soils. The only pest problems for this palm are leafhoppers and the ganoderma fungus.
Light: Needs bright sunlight. Moisture: Tolerates dry conditions once established. Hardiness: USDA Zones 8B - 11. Propagation: From seed which germinates in 2-3 months. Warning - very slow growing! Regular irrigation and feeding will improve growth rate.
Due to its large size, this palm is probably too large and too slow growing for the typical suburban yard. In more spacious landscapes, the Puerto Rican hat palm is best used to line driveways or as a solitary specimen. On large properties the hat palm is spectacular planted in groves where the smooth, massive trunks create a living colonnade that's sure to impress.
This beautiful palm not only tolerates dry areas, making it useful in xeriscapes, but is hardy to zone 8B. (The ones in the picture have survived overnight lows of 16ºF (-9 C) with only slight leaf damage.) The massive leaves and striking trunk combine to make an assertive tropical statement in the landscape. As a bonus, the Puerto Rican hat palm requires little maintenance since its leaves are self pruning.
The Puerto Rican hat palm gets its name from its land of origin, and from the fact that young leaves are collected from the canopy, boiled, dried and indeed woven into hats!