|Sabal palmetto in habitat, Florida|
Sabal palmetto, also known as cabbage-palm,palmetto, cabbage palmetto,blue palmetto,Carolina palmetto,common palmetto,swamp cabbage and sabal palm, is one of 15 species of palmetto palm. It is native to the southernmost lowlands and coastal areas of the southern United States, as well as Cuba, the Turks and Caicos Islands, and the Bahamas.
S. palmetto grows up to 65 feet or 20 metres. Starting at ½ to 2/3 the height, the tree develops into a rounded, costapalmate fan of numerous leaflets. A costapalmate leaf has a definite costa (midrib) unlike the typical palmate or fan leaf, but the leaflets are arranged radially like in a palmate leaf. All costapalmate leaves are about 0.20 inches or 5.1 millimetres across, produced in large compound panicles up to 8.2 feet or 2.5 metres in radius, extending out beyond the leaves. The fruit is a black drupe about .5 inches or 1.3 centimetres long containing a single seed. It is extremely salt-tolerant and is often seen growing near both the Atlantic Ocean coast and the Gulf of Mexico coast.
S. palmetto is hardy to USDA zone 8, and has been reported to have some cold hardness down to 8.6 °F or -13.0 °C, but needs hot and humid summers to grow well. Maintenance of the cabbage palm tree is very easy and very adaptable. The cabbage palmetto is known to tolerate drought, standing water and brackish water. Even though this palm is drought-tolerant, it thrives on regular light watering and regular feeding. It is highly tolerant of salt winds, but not saltwater flooding.
The cabbage-like terminal bud has been eaten as hearts of palm. The bristles on the sheaths of young leaves have been made into scrubbing brushes. The trunks have been used as wharf piles. On June 28, 1776, Charleston patriots under William Moultrie made a fort of palmetto trunks and from it defended successfully against the British in the Revolutionary War.
S. palmetto is a popular landscape plant in subtropical climates and used for its tolerance of salt spray and drought, and is moderately cold hardy. Because of their relatively long establishment period and prevalence on southern ranchlands, few, if any are grown from seed in nurseries. Instead, established plants are dug in the wild with small rootballs since virtually all the severed roots die and must be replaced by new roots in the new location. Most leaves are removed at this time to reduce transpiration. It is the state tree of South Carolina and Florida. Most references rate the species as hardy to USDA hardiness zone 8a. Cabbage palms have excellent hurricane resistance, but are frequently overpruned. Sabal palms normally only do well in hot and humid summer climates.
The growing heart of the new fronds, also known as the terminal bud, gives the tree its "cabbage" name, since this is extracted as a food and tastes like other undifferentiated plant meristem tissue, such as the heart of a cabbage or artichoke. It is one of several palm species that are sometimes used to make heart of palm salad. Heart of palm was commonly eaten by Native Americans. However, extracting the heart kills this species of palm, because the terminal bud is the only point from which the palm can grow,so without this bud, the palm is not be able to replace old leaves and eventually dies.
The cabbage palm is remarkably resistant to fire, floods, coastal conditions, cold, high winds, and drought. Despite this, recent mortality has been caused by Texas phoenix palm decline, a phytoplasma currently found on the west coast of Florida.
S. palmetto trunks appear in two different conditions, which can be confusing (see photo). When leaves die, the leaf bases typically persist for a while, creating a spiky, "basketweave" effect. These remnant leaf bases are called "bootjacks" or "boots", for short. The name stems from the "Y" shape that was reminiscent of devices used to aid individuals in removing boots. Transplanted palms are sometimes deliberately shorn of these bootjacks. Taller specimens are more likely to have lost their bootjacks and appear relatively smooth and columnar. The loss of bootjacks is a natural, if poorly understood, phenomenon, as the palm does not create a leaf abscission zone so the loss of the leaf bases results from some other physical or biological process.
Recently, a new mutant form of S. palmetto has been discovered in southwest Florida, and named as a cultivar Sabal palmetto 'Lisa'. The difference between the 'Lisa' and the wild-type S. palmetto is in the form of the leaf. The 'Lisa' has costapalmate, acute, not pendulous, not filamentose, rigid, not strongly divided, cupped, and slightly undulating leaves. This mutation is beginning to be seen in the nursery trade, as it is just as hardy to cold, salt, drought, fire, and wind as the wild type of the species, but looks different. Seeds from S. palmetto 'Lisa' have a 68% chance of becoming true to type, the other 32% develop as the wild type.