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The BG-Map Hardy Palm Page
By Mark Glicksman
Like many people who live in cold winter climates, I am fascinated by palms. A palm tree is, of course, synonymous with the tropics. Can you think of any movie set in a tropical or subtropical locale that doesn't open with a shot showing palm trees?The Old "Hardiest Palm"
I, like many northern gardeners long for palms. I want to have a palm growing in my garden, not because it will make the winters feel any warmer, but because it provides a link to that warmer world. I'd like to look at those shots of palms on TV and think, "Sure, I've got one of those!". There is no substitute for a palm. Only a palm looks like a palm. You can't simulate it with a plant the looks "sort of like a palm". So... I'll just go out and plant a palm... Oh, but there's one small problem - Palms don't grow in Pennsylvania!... or do they???
Responding to similar desires, gardeners in Britain, the Pacific Northwest of North America, and similar cold and gloomy climes have planted the "Windmill Palm", Trachycarpus fortunei, often referred to as the hardiest of palms. And, indeed it does quite well in those places. It's quite possible to drive down a street in Seattle or Vancouver and see a beautiful clump of these trees growing on somebody's front lawn. So, many years ago, I tried planting a few of these "hardy palms" here in the Philadelphia area. Well, Philadelphia, even though it's at the same latitude as Rome, is much colder than London or Seattle. Those Trachycarpus palms lasted one or two winters and were gone! kaput!Enter the Real Hardiest Palm!
Reading the Journal of The Palm Society one day, I came across a reference to the extreme hardiness of the "Needle Palm", Rhapidophyllum hystrix, a little known palm native to the SE USA. The article stated that this may very well be the most cold hardy palm of all! Fortunately, shortly thereafter, I came across a specimen of this plant at a nursery in Virginia Beach, Virginia (The nursery no longer exists.).
« Author and his Needle Palm in 1995
This very plant has been growing on my front lawn in Glenside, Pennsylvania (a suburb of Philadelphia) since 1985! It has survived some of our coldest and iciest winters of the last century, with days on end of below freezing temperatures, with minimums of -6 degrees F (-21 degrees C). And, it's still in excellent condition. Some years, it even flowers and produces seed.
So, without a doubt, Needle Palm, Rhapidophyllum hystrix is my candidate for hardiest palm on earth!
Characteristics of The Needle Palm
Thank you to Larry R. Noblick, Ph.D. Collections Manager at the Montgomery Botanical Center in Miami for supplying some of the following information, from the Field Guide to the Palms of the Americas
Rhapidophyllum hystrix is a unique shrubby palm - the only member of its genus in the world. It is native to central and northern Florida as well as a few coastal areas of Mississippi, Georgia, and the Carolinas. Both the common and scientific names of this plant are derived from the extremely sharp quills that surround the leaf sheaths - wear heavy gloves or be extremely careful when weeding!Photo of really big needle palms in their native habitat in northern Florida
Needle palm occurs in wet woodlands or hammocks, usually on limestone soils. The flowers are unisexual, with male and female flowers usually on separate plants. So, to produce viable seed, you most likely will need more than one plant. The seeds are brown, about the size of small olives, and covered with interesting whitish hairs (See "Palms at the Morris Arboretum - Pictures in Photo Gallery".)
In my garden, needle palm produces fiber covered stems about 4 inches (10 centimeters) in height. In the wild, old needle palms can produce stems up to 3 feet (1 meter) in height.
The leaves are fan shaped (palmate) and a beautiful shade of glossy green - about 30 inches (75 centimeters) across. As the plant grows, the stems multiply by offsets, so the plant grows in diameter, rather than in height.
In my garden, the overall height of the plant was about 3.5 feet (1 meter) in 1998. In November, 2005, the approximate dimensions were:
It is very slow growing, but worth the wait!
Photos of Needle Palm in Author's Garden, November, 2005
I would recommend Needle Palm for gardens in USDA hardiness zones 6b and above (average minimum winter temperatures 0 degrees F (-18 degrees C) or above. It's probably worth a try in even colder areas. It should be planted in a moist sunny spot. Try to choose the warmest spot in your garden (The place where the snow melts first.). It has landscape value both as an interesting specimen and as a mass.
I use the following regimen to care for my Needle Palm:
Year Round Mulch with well rotted wood chips. Winter Apply an extra mulch of oak leaves piled deep. Spring Remove the extra mulch and any damaged growth. Late Spring Feed with a balanced high organic content fertilizer. and Mid Summer
If you have success with Rhapidophyllum hystrix, you might want to try another hardy palm, "Dwarf Palmetto", Sabal minor. Unlike Rhapidophyllum hystrix, Sabal minor is a member of a genus with many species, including the Sabal palmetto, the most common palm tree in the southeastern states. But, Sabal minor is far hardier.
It is another shrubby palm, with a range extending all the way from southeastern Oklahoma, across the Gulf States, and up into North Carolina. It occurs in rich soils in the understory of broadleaf forests. The stem grows mainly underground, but can sometimes reach up to 6 feet (2 meters) above ground in the wild. The foliage is larger than needle palm, bluish, and not glossy. It is reported to be almost as hardy as R. hystrix and somewhat difficult to transplant.
My Sabal minor was severely damaged during a wicked winter several years ago. It actually disappeared completely for an entire summer! Then, miraculously, it reappeared the following year. It grew slowly for about 5 years after that before it died in a winter that was not particularly cold. I'd be willing to try another one though, perhaps in a different location.
Getting palm seed to germinate can be frustrating and painfully slow. It can take months - or even years for some species. Are there ways to speed up the process? ... Yes!
Chuck Huxford, of The Creative Native, brought to my attention a paper entitled Promoting the Rapid Germination of Needle Palm Seed, published in The Proceedings of the Florida State Horticultural Society no. 106 in 1993 by William J. Carpenter, Eric C. Ostmark, and Kathleen C. Ruppert.
Through their experiments, the researchers identified two different methods, which yielded high germination (80% to 98%) in a short time (1-1/2 to 2-1/2 weeks). The procedures used were very exacting and were described in great detail. But, they can be summarized simply as follows:
Surface sterilize and rinse the seed. Using a sharp knife, remove the embryo cap (a little bump on the side of the seed.) Germinate in a sterile soiless medium at 30 deg C.
Presoak the seed for 7 days in distilled water, changing the water daily. Germinate in a sterile soiless medium, maintaining a daily temperature cycle of 6 hours at 40 deg C, followed by 18 hours at 25 deg C.
Note that Rhapidophyllum hystrix is considered an endangered species, so make certain that you buy from a reputable source. The following is provided for information only and without endorsement.
|Rhapidophyllum hystrix is available from the following online and mail order sources:|
The Chilly Palm Tree Co.
3107 York Farms Rd.
York, SC 29745
Five Branches Nursery, Inc.
4801 S.W. 111th Terrace
Ft. Lauderdale, FL 33328
Note: Retail sales are onsite pickup only. Wholesale sales are deliverable.
4801 S.W. 111th Terrace
680 Crump Farm Road
New Bern, NC 28562
Plant Delights Nursery, Inc.
9241 Sauls Rd
Raleigh NC 27603
fax: (619) 758-4712
A good article on hardy palms is published in the February, 1996 issue of "The American Horticulturist", magazine of The American Horticulture Society. It covers Rhapidophyllum hystrix, Sabal minor, and Serenoa repens, as well as Trachycarpus and some less hardy palms.
Palms in Hungary, by András Neményi, of OMMI in Budapest, covers palm culture in Hungary from A-Z, including history, climates, microclimates, favored regions, species, and winter protection. This information is extremely useful to all of us "Northern Palm Enthusiasts".
The "Palm Lady" is Kathleen Denton of Virginia Beach Virginia. In this article, she shares her varied experience in growing hardy palms in a climate that can be benign, but is often challenging.
Here is an informative article on factors to consider when predicting the hardiness of palms, written by Larry R. Noblick, Ph.D. Collections Manager at the Montgomery Botanical Center in Miami. It is accompanied by two tables laden with palm hardiness observations taken during severe freezes in Florida and elswhere.
My own thought on hardiness is that it is a subject we still don't understand very well. There are many factors to consider beyond the simple one of minimum winter temperature and USDA hardiness zone. After all, parts of Massachusetts and parts of New Mexico are both in zone 7, but their climates and soils are so different that few plants can grow well in both places. Beyond minimum temperature are factors such as length of extreme cold spells, wind and low humidity in winter, mean temperatures in winter and summer, soils, rainfall, sunlight and many more. Saying that a plant is hardy in a particular USDA zone may provide a rough guide, but rough is the operative word. If you are a gambler at heart and don't mind losing a plant (and some money) here and there, go ahead and try pushing the listed hardiness of a plant by a zone or maybe even two.
Of course, don't get carried away. If you live in a climate like the upper midwest of the U.S., you are not going to be able to grow palms outdoors. It's just not a realistic expectation.
One truism that does seem to hold with palms is that bigger is hardier. A larger specimen of any particular species will be hardier than a smaller one. So, try to plant as large a palm as you feel comfortable investing in. In particular, with Windmill Palms (Trachycarpus), once the plant has achieved a trunk height that will keep the crown above the snow, your chances of success increase significantly.
Hardy Palm Links
Other Palm Links
- The European Palm Society - A European affiliate of the International Palm Society (see below.)
- Exotic Gardens Discussion Group - discuss hardy palms, bananas, etc. with other enthusiasts
- PalmsNorth.com - an on-line forum for hardy palm and subtropical enthusiasts
- Virtual Palm Encyclopedia - Published by the Palm & Cycad Societies of Florida (PACSOF) - Lots of scientific information on palm nomenclature, and a huge list of palm links.
- The International Palm Society - Commune with palm fanciers worldwide
- Palm & Cycad Societies of Florida - Hosts of the annual Palm Fest
If you would like to share your experiences in growing hardy palms, please contact me at firstname.lastname@example.org
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