Caryotas: The Fishtail PalmsBy Geoff Stein (palmbob)
October 7, 2010
One of the first palms I fell in love with when I was just getting to know palms were the Caryotas or fish tail palms. Some of these are among the most commonly grown of all the house palms, and here in Southern California, relatively common landscape plants among enthusiasts, though not commonly grown by the rest of the community. I have mixed feelings about these palms now that I have much more experience with them as they have many positives but also some downsides. The following discussion will introduce the reader to these interesting and unique palms as well as discuss their care, both indoors and out.
This photo is of HoOlamuhia Gardens in Hawaii, and shows 5 species of Caryota, all looking great
Caryotas in San Diego Zoo, California
Palms are often divided up into several basic groups depending on their appearance. Most may be familiar with fan palms; those with leaves that are either fan shaped or ‘hand-shaped' with all the leaflets either fused partially, completely or completely separate, radiating in a fan-shaped pattern from the end of the petiole (sort of like the "branch" of a palm). Most of the rest of the palms are pinnate, or feather palms in which the leaflets are arranged along the length of part of the petiole, called the rachis, and resemble a feather, at least in structure. These two basic leaf types include about 95% of all the palms in the world with rest being more complex variations of these two basic leaf patterns. Caryota palms are bipinnate palms, the only palms that have this sort of leaf anatomy. In other words these palms have the basic shape of a feather palm, only there are "side branches" off the main "branch" and all the leaflets come of these side branches. This more complex leaf arrangement makes for some of the most dramatic and beautiful of all the palm leaves. Each leaflet of a Caryota palm is somewhat triangular in shape, sort of the shape of a fish's tail. Hence the name fish-tail palm.
two different species of Caryota, showing the bipinnate leaf arrangement with the 'main' petiole and all the 'side petioles' with the triangular leaflets coming off them
Caryota mitis leaflets
Caryota palms have other characteristics that are not actually unique in the palm world, but certainly the exception rather than the rule. One is that they are monocarpic, which means that once they flower, or at least finish flowering (a process that can take years sometimes), the stem dies. A few Caryotas are suckering, so the entire plant does not die, just the stem that flowered. Most, however, are solitary, so once the tree flowers, one has to replace or at least remove the palm from their landscape or pot. Some palms are relatively fast growing making these some of the shorter lived palms one can grow in cultivation, sometimes living out their entire ‘natural' life in ten to twenty years. This makes them one of the few palms one can often grow and actually experience their entire life span from seedling to death (many palms are so agonizingly slow that if grown from seeds or seedlings, one will be lucky to live long enough to see them in the mature form).
Caryota rumphiana almost done flowering (nearly dead)
Another characteristic of Caryota palms is they have toxic fruits. Most palms around the world are completely non-toxic, but a few have oxylates in the fruits making them a health hazard to pets and children if grown in one's yard. These oxylates are not only toxic to ingest (not highly toxic, mostly incredibly irritating), but toxic to touch even, making cleaning up their mess after fruiting a trickier business. Larger species produce massive quantities of fruit as well, which can create a huge, gooey mess below the palm during the last year of two of its life.
Caryota mitis fruits Caryota rumphiana flowers (right) and fruits (left)
Caryotas are made of fairly hard wood, making them one of the more difficult palms to cut down once they die. Even chain saws struggle to get through this wood. Their roots are also relatively shallow for palms, making them susceptible to blowing over in high winds. Sometimes larger solitary specimens in California just fall over for no obvious reason, though rotting of some its few roots is probably the cause. This is important to remember when considering planting one near a house or other delicate smaller plants.
Caryota urens woody trunk- very hard
Outdoor care for Caryotas is similar to most any other palm though there is a large variation in cold hardiness in the genus, with some being impossible to grow in a cool Mediterranean climate and others being excellent choices for one. All excel in tropical climates. Most are full sun palms eventually but the slower, smaller species do best as understory plants, tending to look sad in full, hot sun. All need copious water and are fairly heavy feeders.
Caryota obtusa leaf fried by severe cold (left); Caryota maxima seedling killed outright in my yard from freeze around 25F (right)
Caryota obtusa showing common chlorotic condition from lack of fertilizer in loamy soil
As indoor palms, spider mites are their primary bane, though low humidity takes its toll as well. Most do fairly well in relatively low light, but the more light (avoid full sun) the better to keep the palms from becoming too etiolated. These are not easy to overwater, but if the soil is not well draining, I suspect rotting them would be possible. Misting them frequently and wiping the leaves down should keep the humidity and spider mite issues at bay somewhat. The larger and/or tropical species probably would not make good indoor palms.
There are about 13 species of Caryota and many have been named and renamed over and over again. Just about every 10 years, one or two new species are discovered and 1 to 2 old species are lumped together. The following are some of the more common and well known species in cultivation.
Caryota maxima has been a bit of a dumping ground for other species that I have collected and grown in the past, now all lumped into this species. Caryota ochlandra and Caryota basconensis, two plants I have grown in the past, are now considered Caryota maxima. It is a medium to tall Chinese, solitary species with the typical concrete-like subtley ringed whitish trunk and drooping, bipinnate leaves. Some recognize this species as separate from Caryota urens, a very similar looking palm, but the lack of any recognizable petiole (leaflets arise off their mini-rachis immediately from the trunk to the tips) sets it apart... barely. Caryota urens have a short petiole without any secondary rachis on them, but otherwise I cannot easily tell them apart. This is a fast growing palm that does fairly well in our cool California climate, but probably prefers a more tropical climate such as south Florida or even better, Hawaii. However, it does come from fairly high elevations in Asia and has some excellent cold tolerance. This is not one of the more common Caryotas in cultiavation.
Caryota maximas in California (grown as Caryota ochlandras)
Two Caryota maxima seedlings sold to me as Caryota basconensis
Caryota mitis is one of the most commonly grown fishtail palms, and is commonly called the clumping or miniature Fishtail Palm. This southeast Asian palm grows up to nearly twenty five feet tall, but in California, struggles to get half that height. In nature it is an understory palm, and probably should be grown as one in the landscape in California since the hot sun and drying winds make this poor plant look horrible when unprotected. It has some cold tolerance (down to USDA 9b), but is not an attractive species when grown near the limits of that range. I have struggled with this species and never had one look good or even survive more than 3 or 4 years. It is an exceptionally attractive species in a warm, humid climate where if forms a lush, dense, feathery clump of greenery that has a long life since it keeps forming new trunks as the old ones die. It makes a half decent indoor palm, but never looks great as one always brown-tipping and struggling with spider mites. Grown in a pot as a patio plant in the tropics it is an excellent specimen, however. Though it is used often as an indoor plant, many indoor Caryotas sold as these are actually clumps of a solitary species (usually Caryota urens).
Caryota mitis in Hawaii (left) and California (right)
Caryota mitis in full sun Los Angeles (left) and a healthy variegated specimen in Hawaii at a nursery (right)
Carytoa mitis in Florida outdoors (left) and in large enclosed space (also Florida- right)
Caryota obtusa (or gigas, depending upon which source lists which as a synonym of the other), or giant fishtail palm, is one of the best landscape palms for large yards and parks. This is a moderately fast growing tree, supposedly obtaining an eventual height of over one hundred feet (though very unlikely to get that tall in many areas of the US, either due to hot, dry winds (west coast) or lightning (east coast). If given protection from the wind, though, it is probably the most spectacular of all the Caryotas, at least in terms of foliar symmetry and beauty. Unlike most other Caryotas, the leaves of Caryota obtusa tend to spread somewhat horizontally and also spread out, unlike the droopy leaf shapes of most of the other Fishtail Palms. This spreading shape allows one to visualize almost all the leaflets individually in a large, lace-like geometric pattern. That along with the palm's staggering size make it one of the most impressive of all the specimen palms. Also unlike other Caryotas, this one starts out with a huge trunk covered with dark, woven fibre. This palm is rapidly becoming the most popular of the large Caryotas and is fairly good cold tolerance as well as better wind tolerance than most. It is still too new in southern California to know what its eventual height will be. How large this palm will get by the time it dies is unknown to me, but its removal should be taken into consideration before one plants it somewhere hard to get to. This species is not completely unique in the palm world, but Catyotas no and C. kiriwongensis are rarer in cultivation with the former being quite cold sensitive so my experiences with it are scarce, and the latter only having been discovered and described in the last 6 or 7 years.
Caryota obtusa dwarfing a Royal palm (left); leaf spread of maturing palm in California (right)
Younger Caryota obtusas (left) and even younger seedling (right)
Carytoa obtusas growing in Huntington Gardens 2004 (left) and 2009 (right) showing growth rate
Caryota obtusa trunks (left) Fibre on younger trunking palm (left)
Caryota obtusa in private garden, California doing well (left) and flowering (right). This palm is probably flowering abnormally early due to some stress (probably something about the lousy California weather)
left shows why Caryota obtusa is such a popular species; right is one of the larger specimens in California (San Diego Zoo)
Caryota rumphiana is a somewhat marginal palm in my area, but a popular and commonly grown landscape palm in the tropics. It is a moderately tall, solitary species with upright, spreading leaves and a nice lacey pattern that does not rival Caryota obtusa, but is much more attractive than the droopy-leaved species.
Two shots of Caryota rumphianas as street trees in Singapore
Caryota urens is probably the most commonly grown solitary palm in cultivation, though its popularity is being surpassed by Caryota obtusa. This is an extremely fast growing species, getting upwards of sixty to eighty feet in under ten years in a relatively cool Mediterranean climate. It has fairly good cold hardiness as well. This is a relatively slender Fishtail Palm in silhouette with arching, drooping leaves. Though one does not get to appreciate each leaflet as in the more spread out species, it is still an attractive palm and a great landscape specimen. It is also sold frequently, often in clusters, as a house palm and it performs fairly well as one for a few years. Then it gets too leggy and spindly from lack of sunlight and needs to be replaced. This is the species most noted for its tendency to fall over unannounced, so placement of this in the yard should take some consideration. Most growers put this in the front yard, near the street, so eventual removal with a crane can be made much more easily.
Caryota urens planting in California (left) and close up leaf shape (right)
Shots of flowering Caryota urens. Right shows tree near a tall building to show mature size
Caryota urens dwarfing toher mature palms California (left); typical Caryota urens trunk (right)
The last two species I will discuss here are two of the most beautiful Caryotas, though neither of them have any cold tolerance and are both basically hopeless in California. However, even in the tropics they are very slow growing and can be frustrating palms. Caryota ophiopellis is commonly known as the Snakeskin Fishtail Palm because of the ornamental reptilian-like pattern on its petioles. I have yet to see a mature Caryota ophiopelis anywhere. This palm is from Vanuatu, which includes several islands in the South Pacific. Caryota zebrina, probably very closely related, and is from New Guinea. This palm is commonly known as the Striped Fishtail Palm and the patterns on its petioles are similar to those of Caryota ophiopelis but even more striking and ornamental. I personally find them difficult to tell apart, though. Both are recent introductions into the palm trade and their popularity initially soared, but has since dropped off a bit as people discover how slow and fussy they are.
Young Caryota ophipelis in Hawaii (left); close up of petiole of Caryota ophiopelis (right)
Caryota ophiopelis petiole (left) and Caryota zebrina petiole (right)... look the same to me
Caryota zebrina Thailand (left) and in pot in Taiwan (right)
There are more species but I know less about them and most are not terribly unique, and are rare in cultivation.