Botany Boy

The genus Butia, the so called pindo palms, are native to the grasslands of southern Brazil into Uruguay, Paraguay, and Argentina. They also are known as jelly palms since their large yellow-orange fruits can be used to make reasonably good tasting jams. They have the added benefit of being some of the more cold tolerant palm trees, taking several degrees of frost before showing signs of distress.

Perhaps the most celebrated of the genus is B. capitata, a palm that has a long history of cultivation in western gardens. This species is a pinnate palm, often called “feather palms”, since their fronds are long feather-like affairs with a central leaf axis (known as the rachis) supporting rows of long, simple leaflets (known as pinnae) extending down its length. As with many commonly grown plants however, its story is quite a bit more complicated than what one would first imagine.

The pindo palm typically grows between 3.5-4.5 meters tall, but can reach 6 meters or more in vigorous specimens. Its trunk is singular and thick, typically between 30-50 centimeters in girth, and very often covered with old petiole bases (leaf stalks) that can persist for years. Clear trunks are grey in color and patterned with old leaf scars, giving it a horizontally banded look.

The fronds are pinnate in form, growing between 1.5 and 3 meters long, and arch in a recurved shape back towards the trunk, giving this palm it’s signature look. Their overall color is commonly blue-grey, but can be light green depending on environmental and genetic factors. The rachis supports opposing rows of regularly arranged pinnae up to 75 cm long each, the longest being mid-frond, and held in a pronounced “v” shape. The petioles are armed with abundant, long teeth, as can be seen in the persistent leaf stalks. Plants grown in poor soils or more sun tend to be more compact than average specimens.

Flowering normally commences in late spring to early summer. The yellow-cream flowers grow in large, stalked bundles which can be up to a meter long with many side branches. The ovate to rounded, brilliant orange fruits are borne generously in tight clusters from late summer into fall. They average between 2-3 cm across.

The “true” Butia capitata is native to a very confined area in the coastal states of Bahia and Minas Gerais in central Brazil. Now for that aforementioned complexity about this palm. Apparently most of them cultivated around the world are NOT B. capitata, but rather are a different species, the most probable candidate being the recently named B. odorata, a native of the coastal areas of Uruguay and the adjacent state of Brazil, Rio Grande do Sul. To complicate matters more, several species of Butia from the surrounding region, notably B. eriospatha (confined to southern Brazil), B. paraguayensis (a dwarf widespread species), and B. yatay (a taller growing palm with a thicker trunk) are being grown as well. Butia species readily hybridize, so it is also possible that the great range of variation seen in cultivated plants is in fact an artifact of interbreeding. Go figure.

All Butia species are native to grasslands and dry open forests ranging from southeastern Brazil, into Uruguay, Paraguay, and northeastern Argentina from near sea level to over 1000 meters elevation. They can be found in the Cerrado region of Brazil (an area comprised of various types of savanna where woody species are plentiful), sandy-soil grasslands, pasturelands, the restingias ecoregion (dry coastal forests of the Atlantic coast) and campos (grassy plains with few trees). Species growing in the inland/upland areas are subject to fairly severe frosts with little protection, and so can be assumed to be far more cold tolerant than coastal populations.

If it is true that most pindo palms in cultivation are derived from B. odorata stock, a species found only in the restingias of coastal Uruguay and Brazil, one would expect these plants to be rather frost tender. Remarkably however, most sources consider typical plants in the trade to be cold hardy to at least -10 C (14 F) without any winter protection. With some protective measures, plants have been grown in far colder climates, apparently being rather commonly seen on the eastern coastal plain of the USA as far north as North Carolina with outlying specimens being grown even up to Washington, D.C., New Jersey and Long Island, in New York State.
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Surly the largest commonly grown ornamental palm in the world is the Canary Island date palm, Phoenix canariensis. A close relative of the true date palm, P. dactylifera, this species is much more widely grown due to its ability to live in a broad range of climates and soils. Beyond that, this palm is truly stunning as a mature tree.

Phoenix canariensis is a massive palm with a single trunk growing typically up to 20 meters, but vigorous specimens have reached twice that height. The thick trunk is up to nearly a meter across with a wide, bulbous flaring base. It is prominently marked with petiole scars that have a stacked appearance, and is usually light brown in color.

The fronds are pinnate, growing from 4 to 6 meters in length on mature trees. The individual leaflets (called pinnae) are simple and narrow, between 20-40 centimeters long each. The central shaft of the frond, the rachis, widens at its base and is armed with long, sharp spines. The overall appearance of the fronds is like a long feather. A mature specimen can hold a hundred or more fronds at one time, forming a dense, nearly rounded crown up to 10 or more meters across. Like other palms the petiole bases can persist for some time, an attribute particularly noticeable on pruned specimens.

Flowering starts in early spring. The bright orange branched flower scapes are born abundantly, but remain tucked within the the crown even in at full maturity. These palms are dioecious, meaning male and female flowers are found on separate trees. Fruits are ripe by fall or early winter, and though fairly large, are not particularly fleshy, and so do not make a good date for eating. A single large seed is contained in each fruit.

P. canariensis is an endemic of the Canary Islands, a volcanic island chain off the southwest coast of Morocco in the Atlantic Ocean, and though owned by Spain, are largely self governed. This palm is found throughout the main islands, however its distribution is scattered and localized due to centuries of human activity. The largest remaining populations are found on La Gomera. The introduction of exotic Phoenix species (especially P. dactylifera) has put the remaining populations at risk since these palms easily interbreed, creating hybrid trees that can be difficult to distinguish from wild ones.

They can be found in a wide range of habitats, typically in dry subxeric Mediterranean areas and more rarely in wet cloud forests, known locally as laurisilva, consisting of broadleaf subtropical evergreen trees. In some areas P. canariensis is the dominant species, and these communities are known as palmerales. Nowadays these once natural associations are highly influenced by humans who have introduced exotic species or expanded them by planting more palms. This species grows from sea level to around 600 meters elevation in its native habitats. For more about this palm in its native habitat please read this fascinating article from the journal of the International Palm Society: Phoenix canariensis in the wild.

In of spite being from the relatively low elevations of subtropical islands, the Canary Island date palm is remarkably cold hardy. Most sources state large trees can take -10 C (14 F) for brief periods and rebound, though fronds are damaged at much higher temperatures, taking no more than a couple degrees of frost before die-back begins. Nevertheless, consistent reports of them surviving in USDA cold hardiness zone 8 persist, at least in areas where summers are hot. Having said that, as long as the average temperate remains a few degrees above freezing in winter, this species seems to hold on. Reports of specimens growing in cold weather latitudes also abound, for instance the warmest parts of the British Isles (including London), Tasmania, and even the coastal areas of British Columbia, Canada and along the coasts of Washington and Oregon in the US if given protection in winter. On the other hand, it is able to live in truly tropical places as well, making it one of the most temperature resistant palms in cultivation.
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