The Journal of The European Palm Society - No. 48

C h a m a e r o p s

48

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C o n t e n t s

A r t i c l e s :

Cold-Hardy Palms for Temperate European Landscapes by David A. Francko page 5Trachy Troubles by Nigel Kembrey page 9Hardy Citrus by Vince Carr page 12Early Conclusions on Germinating Parajubaea by Angelo Porcelli page 14New Palm Book Available page 18Web Update page 19

S t a n d a r d s :

Editorial by Tobias W. Spanner page 3Letters by our members page 23Shop get back issues and more page 23

Cover: Phoenix canariensis on the terrace of the fabulous Villa Sainte Claire, the former estate of famous American author Edith Whartonhigh above Hyères les Palmiers, France.Photo: Tobias W. Spanner and Lauri Coulombe

Chamaerops is the quarterly journal of The European Palm Society. The European Palm Society (EPS) is affiliated to theInternational Palm Society and was founded in 1991. The EPS is a nonprofit organization dedicated to sharing information aboutpalms and other exotic plants across the continent of Europe. The main goal of the EPS is to communicate with other enthusiaststhrough Chamaerops, the EPS website, or personally at Society meetings, in order to share ideas and knowledge of the successfulcultivation of exotic plants. Above all, the EPS and Chamaerops are run by members, for members.Issue no. 48, published in May 2004

Editor Tobias W. Spanner (Germany) mail@palmsociety.orgMembership Organizer Tony King (UK) membership@palmsociety.orgLanguage Editor Lauri D. Coulombe (USA)French Translator Yann Corbel (France)German Translator Jörg Witticke (Germany)Layout, Design ultracondensed.com (Germany) webmaster@palmsociety.orgPrinters Simmons Printers Ldt. (UK)

Special thanks to all our contributors.Please send manuscripts and pictures by mail or e-mail.Computer files are most welcome. Pictures can be send asprints, negatives, slides, on floppy, CD-ROM or by e-mail.Please send to: The European Palm Society, Tobias W. Spanner,Tizianstr. 44, 80638 München, Germany

To join the EPS please contactTony King - 34, Keats Avenue - Romford, Essex RM3 7ARUnited Kingdommembership@palmsociety.org

Membership rates:Chamaerops only: 1 year £15. Online only: 1 year £12, 2 years £20, 3 years £24. Chamaerops & Online: 1 year £20, 2 years £36, 3years £48. Upgrade: Members currently off-line can upgrade their membership to 'Chamaerops & Online': 1 year +£5, 2 years +£10,3 years +£15. For any online membership queries please visit www.palmsociety.org

The European Palm Societyc/o The Palm CentreHam Central NurseryHam Street, HamRichmond, Surrey, TW10 7HA - United KingdomPhone: +44 20 8255 6191Fax: +44 20 8255 6192mail@palmsociety.orgwww.palmsociety.org

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E d i t o r i a l

Very exciting news has reached me recentlyfrom China, where a second population ofTrachycarpus princeps, the Stone Gate Palm, hasbeen discovered recently. From leaf samples Ireceived I have been able to confirm its identitywithout doubt. Hopefully, over time, morepopulations will turn up, which will make theconservation status of this rare species a little lesscritical. There are also rumors going around abouta Trachycarpus found in northeastern India thatcould possibly turn out to be T. princeps.Unfortunately, I have not had the chance to seeany material yet, so its status remains unclear forthe moment.

Please have a look at the special Trachycarpusdouble issue of Chamaerops 35/36 (back issuesare still available at ̈ 6.25/£4, see last page) for thefull story on the discovery of T. princeps. Despitemany years of tireless efforts by various people,seeds of this elusive and hardy plant from thefoothills of the Himalaya in western Yunnan,China have only very recently started to becomeavailable for cultivation in very small numbers. Iam happy to report that the EPS has obtained agood number of fresh seeds that have been donatedto us for distribution to members. We would liketo give FREE small collector packets of these awayto every member contributing an article toChamaerops or a letter to our letters page. So,please grab your keyboards and start typing. Wewill try to match the number of seeds sent outaccording to the size and effort of yourcontribution. Have a look at the Editorial of issuenumber 45 if you need some guidelines for yourcontribution. If possible, please send material tous by e-mail: mail@palmsociety.org

It seems quite popular with long-time palmenthusiasts to muse on the fact that only about 15years ago, the number of good books available onpalms was barely enough to press a herbariumspecimen. Nowadays, at least my book shelves arecroaking under the weight of the literature that

has seen the light in recent years. This past yearalone, three remarkable new books have becomeavailable.

David Francko’s Palms Won’t Grow Here andOther Myths has filled a long standing gap for acomprehensive and well researched book on themost cold hardy palms. You can find hisintroduction to the hardiest types in this issue.

Robert Lee Riffle and well known Palm Societymember Paul Craft with their new Encyclopediaof Cultivated Palms have set a new standard for acomprehensive guide to palms. They discuss manyspecies that have gotten little or no coverageelsewhere and their picture section is quiteamazing, though I was a little disappointed withthe research in some of the texts. See this issue formore information on their book.

Finally, Martin Gibbons’ most recentpublication, A Pocket Guide to Palms, has hitbookstores recently. It is an excellent choice forbeginners and a good reference book that comesin a format you will actually be able to take alongtravelling.

Since we carried such a wealth of articles onthe Palmetum de Tenerife in recent issues, here isa nice page to see the amazing growth rate of a fewpalm in that fabulous garden: http://personal.telefonica.terra.es/web/tenerifepalms/palmetumnews/palmenews.html

Carlo Morici writes about the sad state of theproject these days, that for political reasons “it isstuck. Nothing happens. Basic maintenance goeson but it is still closed to the public. Palm speciesthat have survived are doing great. Rare palms areflowering and fruiting for the first time this year;for instance, Jubaeopsis, Bentickia nicobarica,Bismarckia, Syagrus botryophora, Cryosophila,Pritchardia spp., Hyophorbe indica, and CubanCopernicia”.

One can only hope that politicians there willcome to their right minds on the value and fantasticpotential of this garden. T.S.

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C o l d - H a r d y P a l m sf o r T e m p e r a t e

E u r o p e a n L a n d s c a p e s

By By David A. Francko, Professor and Chair, Botanydepartment, Miami University, Oxford, OH 45056(franckda@muohio.edu)

Palms, Bougainvillea, Oleander, and othersubtropical ornamental species are landscapingmainstays in warm-winter areas of Europe anddefine that “Mediterranean look” known aroundthe world. But if you live in colder areas wherewinter temperatures frequently drop well belowfreezing, you may believe that these warm-climateornamentals are beyond your reach. After all,everyone knows those things won’t grow here! Butconventional wisdom about what will and will notsurvive and even thrive in cool-to-cold-winter partsof Europe (approximately USDA Zones 6 through8a) is incomplete at best and sometimes flat wrong.For example, although most of the world’s roughly1500 palm species are tropical or subtropical intheir distribution, at least 100 species easily survivefreezes down to 20°F (-7°C), and a surprisingnumber will even survive occasional bouts of sub-zero Fahrenheit (below —18∞C) cold (Gibbonsand Spanner 1999; Francko 2000; Francko andWilson 2001: Francko and Wilhoite 2002)!

In Palms Won’t Grow Here and Other Myths:Warm-Climate Plants for Cooler Areas (Timber

Top left: Trachycarpus princeps is doing well in cultivation. Photo:Tobias W. Spanner. See Editorial.

Top right: Dwarf palmetto (foreground), needle palm (left rear)and southern magnolia ‘Little Gem’, Upham Palm Court, MiamiUniversity campus, Zone 6a, November 2002.Middle left: Same plot in January 2003Middle right: Dwarf palmetto (S. minor)Bottom: Chamaerops humilis (Mediterranean fan palm), UphamPalm Court, Miami University campus, Zone 6a., summer 2002.

Press; 2003), I document more than 300 woodyand non-woody warm-climate ornamentals thatsurvive at least 0°F (-18°C), in the ground all yearround, with minimal winter protection. Theseinclude palms, other broadleaved evergreen treesand shrubs, deciduous flowering species such ascrape myrtles, bamboo, cacti, agaves, andtemperate bananas. The book describes how toevaluate your landscape’s microclimates, how tointegrate warm-climate species into an existingtemperate landscape, and which cultivars work bestunder your conditions.

The take-home lesson of my book is simple:even if you live in a cold-winter area, yourlandscape can have the bold variety in form andfunction associated with warmer climes. So, if youwant to create a ‘tropical looking’ paradise in yourtemperate yard or merely want to incorporate apalm or other dramatic specimen planting to anexisting landscape, go for it! To get you started,here’s a capsule description of some (but by nomeans all) of the palm species that are adaptableto colder European climates as well as traditionalPalm Country, in roughly descending order of coldtolerance.

When purchasing palms, it’s best to acquirelarger containerized or balled-and-burlappedspecimens with dense root balls. The palms belowmay be grown in any soil type. Watch for droughtstress during the two to three year establishmentperiod, and modest winter protection is a mustmost years for best foliar overwintering (heavymulching/antidessicant spray). Hardinessinformation below is for established plants. The

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Top left: Washingtonia filifera (California fan palm), UphamPalm Court, fall 2002.Top right: Foliage and flowers of southern magnolia (M.grandiflora; ‘Brackens Brown Beauty’), author’s home landscape,Oxford, OH, Zone 6a.Middle left: Crape Myrtle ‘Acoma’ (white flowers) and ‘Tonto’(magenta flowers) in front of ‘Edith Bogue’ Southern Magnolia,near Pearson Hall on the Miami campus, Zone 6a.Middle right: Gold Dust Plant (Aucuba japonica ‘variegata’), CoxSecret Garden, Miami University campus, Zone 6a.Bottom left: Phyllostachys aureosulcata var. aureocaulis nearPearson Hall, summer 2002Bottom left: P. nigra (black bamboo)

hardiest of the cold-hardy palms are clump-form, meaning that they form at best a short trunk,but several true palm trees are very cold tolerantas well.

Needle Palm (Rhapidophyllum hystrix):Hardiest clump forming palm, no damage to —18°C (0°F) even in first year specimens, althoughspear leaves are sometimes killed. Survives —30°C

(-22°F) with defoliation; grows slowly toperhaps 2.5 m tall/broad in Zone 6b; native to SEUSA (Figs. 1a, b and 4). This palm is as hardy asthe southern magnolias and tree hollies, but bestout of direct winter wind/sun. Partial sun to fullsun but will take some shade. Exceptionallybeautiful deep-green leaves with gray-greenundersides. In areas with cold but dry winterclimates, try the Mazari Palm (Nannorhopsritchiana), a Middle Eastern native that may rivalneedle palms under such conditions.

Dwarf Palmetto (Sabal minor) and LouisianaPalmetto (S. “Louisiana”): Many varieties andputative ecotypes; second most hardy palm, littleleaf burn down to 0oF, defoliates somewherebetween — 5° and —10°F, but has undergroundbud tissue recovered down to —31°C (-24°F) inWichita, Kansas. Slow grow to perhaps 5 ft. talland broad in Zone 6 (Figs. 1a,b and 3). Anyrelatively sheltered site, even very wet.

Windmill Palm (Trachycarpus fortunei / T.takil): Probably hardiest tree palm; survived —26°C (-14°F) with defoliation in our experiments,with leaf burn beginning about —13°C (-8°F),and major defoliation around —18°C (0°F), butbasal parts of most leaves remain green well belowzero F. In winter, protect the trunks and foliage

with heavy leaf litter to add several degrees ofhardiness and help keep water out of crown cavityin winter. Ideal choice for cool marine climates;large specimens grace coastal British Columbia,Canada and the British Isles. Tolerates heavy soils,full sun to partial shade.

Cabbage Palmetto (Sabal palmetto) and relatedspecies: The State Tree of Florida and SouthCarolina may ultimately prove as hardy if not moreso than windmill palms! This is the ‘real’ palmtree, familiar to everyone who visits the Floridapeninsula or the Caribbean. In our Ohioexperience (Fig. 3) and that of enthusiasts in Zone6 parts of the Cumberland Plateau of Tennessee,leaves undamaged down to low single digits F, andsome foliage still green below zero ∞F (-18∞C).Mature, trunked specimens known in Zone 7a/6b, and trees in these areas frequently survive sub-zero ∞F temps. Rapid grower; even if partiallydefoliated will produce crown of 4 to 5 large fanleaves by summer, so can look more impressive asa juvenile than a mature S. minor. Takes manyyears to form a trunk. In cold-winter areas, best toplant large (15 gallon and up) trunkless ratherthan transplant trunked specimen. In winterprotect like windmill palm. Full sun best and willtolerate saline soils. Sabal “Birmingham” may proveto be the world’s most cold hardy tree palm. Stillrare in commerce. Believed to be a hybrid betweenS. palmetto and S. minor, an established specimenin Zone 6b Tulsa, Oklahoma is ca. 3 m tall andbroad, has only minimal leaf damage down to —13°C (-8°F) and has survived -26oC (-14oF). TexasPalmetto (S. mexicana (S. texana)) and BrazoriaPalmetto (S. x texensis) also do well in dryer areaswith cool winters.

Mediterranean (European) Fan Palm(Chaemarops humilis): This beautiful, often multi-trunked palm is familiar to residents around theMediterranen Sea and in similar climatic areas ofthe world (e.g., Southern California and theAmerican South). But this species is also extremelycold hardy, with foliage that is undamaged downto perhaps the mid-teens F (ca. —10°C); smallwell-mulched specimens easily survive —18°C(0°F) or even a bit colder (Fig. 5).

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Blue Hesper Palm (Brahea armata) andChilean Wine Palm (Jubea chilensis): Both of thesetree palms, native to Baja California and cold desertareas of Chile respectively, are relatively hard tofind in commerce but worth the effort, especiallyin areas that rarely drop below about —10°C inwinter. J. chilensis, although adapted to dryclimates, does well in the heavy, wetter clay of theSoutheastern U.S.

California Fan Palm (Washingtonia filifera)and Mexican Fan Palm (W. robusta) are ideal fordryer areas in the southwestern U.S. andclimatically similar areas of Europe. W. robusta,despite the name, is less cold hardy than theCalifornia fan palm and defoliates around —9°C(15°F) W. filifera foliage (Fig. 6) will take severaldegrees more cold, and both species readily survive—18°C (0°F) and even below with defoliation.As such, Washingtonia is often grown in cold-winter areas as a ‘chainsaw palm’. When foliagedies, cut off dead leaves, spray a little fungicideinto the crown cavity, wrap the trunk (especiallythe top of crown) to exclude water, and mulchbase heavily. In the next growing season you’lldelight in a full crown of 8 to 10 leaves that regroweach season. Trunked specimens up to 2.5 m inheight exist in some Zone 6b areas. An interspecifichybrid called Washingtonia x filibusta is nowentering the market and is said to be more coldhardy than either parent.

Jelly or Pindo palm (Butia capitata): Perhapsthe most cold hardy feather-leaf palm species,defoliates in mid-teens ∞F but survives muchcolder temperatures with heavy mulching.

Non-palm companion species: There areliterally hundreds of viable woody and non-woodywarm-climate plants that create a tropical look butare in fact cold-winter hardy. I focus here on just acouple specimen plants that would be on anywarm-climate landscaper’s Top 10 list.

Southern Magnolia (Magnolia grandiflora):The signature tree of the American South isavailable in numerous cold-hardy cultivars suitablefor USDA Zone 6 and even colder conditions. The

glossy dark green evergreen foliage with large,fragrant white flowers in late spring throughsummer cannot be beat (Fig. 7). More than twodozen cultivars of Crape Myrtles (Lagerstroemiaindica) are root-hardy through Zone 5 and providemassive, colorful blooms from midsummerthrough frost in full sun (Figs. 8 and 9). Many ofthese varieties are remarkably cold hardy, and withcare can easily be grown as small trees withexceptional exfoliating bark even in Zone 6. Forshady parts of your landscape try the Gold DustPlant (Aucuba japonica; Fig 10) or one of thenewer cold hardy Camellia varieties now on themarket (Fig. 11) and available via mail order.Finally, no tropical-looking European gardenwould be complete without temperate bananas andbamboo. The Japanese Fiber Banana (Musabasjoo) is root hardy with mulching through Zone5 and perhaps even colder and reaches almost 3m in height each growing season (Fig. 9). Althoughmany cold hardy bamboo varieties are fairlyaggressive runners in warm-winter climates, theyare much more easily controlled in cold-winterareas. Try Phyllostachys aureosulcata var.aureocaulis (Fig. 12a) or Black bamboo (P. nigra;Fig 12b ).

R e f e r e n c e s

Francko, D.A. 2000. Effect of microclimatevariation on cultivation of cold-hardy

palms in Southwestern Ohio. Palms 44(1):37-46.

Francko, D.A. 2003. Palms Won’t Grow Hereand Other Myths: Warm Climate Plants for

Cooler Areas. Timber Press: Portland, Oregon,USA and Cambridge, U.K., 308 pp.

Francko, D.A. and K.G. Wilson. 2001. TheMiami University Hardy Palm Project.

Rhapidophyllum Winter 2001 Issue:12-15.Francko, D.A. and S. Wilhoite. 2002. Cold-

hardy palms in Southwestern Ohio: Winter damage, mortality, and recovery. Palms

46(1):5-13.Gibbons, M. and T. Spanner. 1999. Palms in

temperate climates. Palms 43(3):91-93.

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T r a c h y T r o u b l e s

By Nigel Kembrey

We all love Trachycarpus; after all, it is thecornerstone palm in many parts of the world wherewinters are cold with frost and snow and summersare cool. But what of its future? We are fortunateenough to have been introduced to several newspecies to add to those that we already grow. Thesepalms stand proudly in our gardens: T. takil nextto T. fortunei, T. fortunei next to Waggie. Soon T.princeps, T. latisectus, T. nanus and T. oreophiluswill hopefully adorn our gardens too.Unfortunately, these palms hybridise all too easily,and with so many palms now being planted, itseems that the seed and subsequent generations ofpalms from our home grown collections will beanything but pure. You may think this is a newproblem, but Trachycarpus have been planted inour botanic gardens for 150 years, and, as thosewho follow the online forums already know, somelively debates are already raging over what is andwhat isn’t true Trachycarpus.

If there is any doubt about the problem ofhybridisation, then look at the confusion brewingover Trachycarpus takil as a prime example of whatis likely to happen in years to come. Having beendescribed by Martin Gibbons and Toby Spanneras very much like Trachycarpus fortunei but largerin all its parts with a curious, twisted hastula, thispalm was supposedly lost to cultivation betweenthe years of 1887, when some seed from India wassent to Beccari in Italy, and 1994, when seed wasbrought out of India by the aforementionedexplorers Martin Gibbons and Toby Spanner. Theonly known plant to exist in cultivation was a maleTrachycarpus takil in Rome Botanic Garden grownfrom the original Beccari seed. Suddenly, long lostT. takils are popping up all over the world. ACanadian enthusiast recently posted pictures of hisTrachycarpus, which had the most curious, twistedhastulas I have ever seen, and yet this plant was

too old to be grown from the seed distributed fromIndia in 1994. There is a large Trachycarpus atLamorran that, I believe, Martin Gibbons hasinspected and confessed that it appears very muchlike a T. takil. How can this be when they areextremely unlikely to be pure T. takils? What isthe explanation?

The tried and trusted explanation is thatTrachycarpus fortunei is an extremely variablespecies and all of these traits are within its naturalrange of variation. Indeed, a number of growersof young T. fortunei plants have claimed to observethe twisted hastula and creeping of the youngplant. This, however, leads to another question thatI will raise later. It should also be pointed out thatthe twisted hastula does not appear to manifestitself in all T. takils grown from Indian seed, as ofyet. The T. fortunei itself is also very variable insize, a huge T. fortunei being documented in theEuropean Palm Society journal several years ago.

I believe there is another explanation for thesevariations. In the Victorian planthunting era manyTrachycarpus were brought back from China andIndia, and some of these palms survive today. Ihave already mentioned the Rome Botanic GardenT. takil, but what happened to the rest of the seed?What not many people know is that although T.takil was first identified as a separate species byBeccari from plants grown from that seed in 1887,the plants had already been incorrectly identifiedas Trachycarpus martianus, and seed was sent backfrom India between 1830 and 1850 by MajorEdward Madden and almost certainly planted inour parks and gardens at that time. Clearly otherplants also found their way into European gardens.What became of them? These palms were probablyplanted in proximity to other Trachycarpus speciesin the late nineteenth century and hybridised. Weare fortunate today to be able to easily buy seedfrom all over the world, but early in the twentieth

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Trachycarpus takil, heavily laden with fruit, Naini Tal, UttarPradesh, India. Photo: M. Gibbons & T. W. Spanner

century, with war and closed borders, seedwould have been much harder to come by, andmuch seed would probably have come from thesevery same palms in European botanic gardens. AsTrachycarpus hybridises readily, it is likely that theseed collected from early T. fortunei was in factoccasionally cross pollinated with other speciespresent at that time. It is likely that a number ofmature Trachycarpus in our botanic gardens todayare F1 hybrid Trachycarpus produced from thosefirst Trachycarpus palms introduced in theVictorian planthunting era.

I collected seed from below some large andbeautiful mature Trachycarpus at AbbotsburyBotanic Garden 6 or 7 years ago and was amazedat the variation in the plants that grew. Whilst themajority are regular T. fortunei, some have bizarrehastulas, some creep, some are burnt by frost at—5°C , and two plants have leaves that detachwhen the leaf dies. One only has to wanderamongst the much more consistent young T.fortunei grown from pure Chinese seed at the PalmCentre to realise that something is very different.Is it possible that these unusual palms are F2 hybridTrachycarpus and not T. fortunei at all? After all,F2 offspring of hybrid plants of any species willdisplay considerable variation that is not apparentin the F1 generations. Very often the variabilitygrows with each successive generation. Thisvariation in the offspring could well be a clue as tothe genetic make up of those old Trachycarpusgrowing in our parks and gardens and provides avery strong explanation as to why people arefinding palms with T. takil-like traits, and alsoexplains the considerable variability generallyobserved in the T. fortunei species.

This brings me to the question regarding T.fortunei raised earlier. Exactly how many of theplants that we grow and regard as T. fortunei are,in fact, hybrids? A recent discussion on the PacificNorth West forum centred on an enthusiast whovisited China and claimed to have discovered T.takil has led me to an alarming conclusion. Hefound Trachycarpus so consistently big and

different that he believes they fit the T. takildescription of “larger in all their parts with a baretrunk”. If we go along with the scientific theorythat Trachycarpus as a single species evolved overmillions of years all along the Himalayan foothillsinto several different species , then clearly theycannot be T. takil. So what are they? My ownconclusion (contentious though it may be) is thathe has found true T. fortunei unaffected byhybridisation, which, like T. takil, are larger in alltheir parts. Having grown up with T. fortunei as avery variable species and faced with such a largestand of trees in habitat, this would be an easymistake for any enthusiast to make. Personally, Ifind this all very alarming, because if myobservations are correct, the evolutionary processthat has created these magnificent palms overmillions of years has been reversed in a couple ofour generations.

Whether my historic supposition is right orwrong, with the array of species now beingintroduced, this is most certainly what will happenin the future, putting the individual species verymuch at risk.

Clearly, the only way to preserve each and everyone of these species is to preserve them in theirnatural habitat. Fortunately, they grow in pocketsall along the base of the Himalayas and areseparated by long distances, which is nature’s wayof preventing cross pollination. The main threatis from man; but, with the international palmtrade and the income that is now derived from theseed, hopefully the local people will see the valuein preserving these beautiful palms.

From our point of view, provenance of seedshould be taken very seriously. For example, it isno good picking seed from a Trachycarpus takil ina London garden in 10 years time and selling it asTrachycarpus takil seed, for two reasons. First, theseed is likely to have crossed with any number ofTrachycarpus in close proximity. Second, by notbuying authentic seed from India, the market forseed will drop, making it more likely that theIndians will cut down the trees. As palmenthusiasts, we can all do our share to preserve the

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species. First, we can document what we growand do our best to establish provenance of theplants we buy before we buy them; and, second,we can ensure that we continue to buy seed fromauthentic suppliers, sourced from the lastremaining true stands to ensure the guardians ofthese palms have a financial interest to protect theirassets and preserve these wonderful trees forposterity.

Finally, Martin Gibbons tells me that he andToby Spanner are writing a detailed book on thegenus, although it is not known when it will go topress. I for one would welcome this addition tothe palm library, and I am sure it would clear up alot of misunderstandings concerning thesewonderful palms, so let’s all hope it gets publishedin the near future, as I am sure it would make afascinating read.

(There is still some field and taxonomic work tobe completed before we can attempt to bring this bookon its way, so please don’t be looking out for it toosoon. ed.)

H a r d y C i t r u s

By Vince Carr, Northolt, Middlesex, UK

Palms still give me a buzz. At the base of myfemale Trachy are numerous seedlings dating fromSummer 2002 and they remind me of how I usedto admire the self sown Phoenix at street level alongthe golden coasts of Spain, back in the 1970's whenI first paid them a visit. What I also remember arethe olive trees and the bamboos, which are nowcommonplace in garden centres throughout theU.K., as are many species of palms.

My last birthday present to myself was a dearlittle Phoenix roebelenii, about 60 cm tall, whichis currently overwintering in my frost freegreenhouse with some Hibiscus syriacus, assortedAgave, Aloe, Opuntias, Echinocactus grusonii andDicksonia antartica. The olives and the Yucca alllive outside with the Trachys and Musa basjoo, butthere is something of a botanical gap, indeed averitable chasm; let me explain.

My first venture abroad was on one New Year'sEve in the 1970's on a long weekend toTorremolinos in Andalusia. After sitting in asnowbound aircraft at Luton Airport for 6 hoursuntil finally we were able to take off, it was arevelation to leave the plane in Malaga in thewarmth of a southern Spanish evening. We wentout for dinner in Torremolinos and walked throughstreets lined with Seville Orange trees, the fruit ofwhich were trodden underfoot without commentby assorted holiday-makers.

That's when it hit me. Why can't we groworanges and lemons outside in the U.K.? Don'tbe silly, for the same reason that we can't growpalms outdoors too. Well, that myth wasdemolished in the fullness of time, wasn't it? Sowhat about the citrus then? I did not try anythingfor a few decades, until I joined the RoyalHorticultural Society in Autumn 2002 and was

13Chamaerops No. 48

reading through the advertisements at the rear oftheir journal, The Garden. There it was in blackand white: Hardy Citrus, from Jungle Gardens.

Apparently, in the late 1800's, controlledcrosses were made between the hardy JapaneseBitter Orange, Poncirus trifoliata, and the sweetorange Citrus sinensis, with the cross beingpopularly known as Citrange. In 1909, theCitrange was crossed with the Kumquat and theresulting cultivar was called the Citrangequat.There also exists a cross between Citrange andCitrus limon, the lemon, with the resulting cultivarknown as Citremon.

Needless to say, these hardy citrus plantsproduce fruit that is somewhat lacking in thesweetness department, but there have been furthercrosses in attempts to improve the sweetness andsome of these are now available.

I well remember the excitement I felt when Ibought my first Trachy and planted it in thegarden. I felt the same sensation when plantingmy first olive, tree fern, etcetera. Now I have thesame sense of pleasurable anticipation whilstwaiting for Spring 2003 proper and the deliveryof my first two Citrus plants.

My first variety is a Citrangequat Thomasville,which is described as a sweet and juicy fruitingvariety and the result of a cross between Citrangeand Kumquat. The description continues:“supplied as a 1 litre plant, the tree is vigorous,erect and very ornamental with mostly trifoliateleaves and good cold resistance —10∞Cunprotected and —15∞C with crown protection.The oval fruit resembles the Kumquat, acidic butbecoming edible when fully mature, althoughrelatively seedy. It is very juicy, valued for eatingout-of-hand and for juice drinks”.

My second variety is a Citremon, supplied as a1 litre plant and described thus: “The Citremon isa Citrange crossed with Grapefruit and crossedagain with a Lemon. Another good lemonsubstitute, a bit more bitter than the IchangLemon. Hardier though, to —10∞C”. For the first

3 years these plants will need to be overwinteredin a frost free greenhouse but then they may beleft out for the entire year. I thought that I wouldstart off with just two plants to see how I get onand then if all goes well I plan to try some othervarieties in the range.

I list below some Internet links which I hopewill enable any interested EPS members to obtainsome further information.

h t t p : / /www. saa l f i e l d s . f re e s e r v e . c o.uk /citranges.htm

(see also Poncirus and Ichang Papeda andCultural Advice) A valuable resource on HardyCitrus cultivation.

http://gmr.landfood.unimelb.edu.au/Plantnames/Sorting/Citrus.html

This University of Melbourne multilingual,multiscript, plant name database 'Sorting CitrusNames'.

http://members.aol.com/agrumivos2/agrfrose.htmThis is the Agrumi Voss web site in Germany

about Frosth‰rtere Citruspflanzen. It containssome English descriptions but it would probablybe difficult to order for those EPS members whodon't speak German.

http://www.junglegardens.co.uk/PlantOrdersThis is a UK company called Jungle Gardens

based in Watlington Oxfordshire who supplyHardy Citrus plants as well as other items.

14 Chamaerops No. 48

Parajubaea cocoides enjoying the sunshine in Quito, Ecuador.Photo: Tobias W. Spanner

E a r l y C o n c l u s i o n s o nG e r m i n a t i n g P a r a j u b a e a

By Angelo Porcelli, Bisceglie (BA), Italy

The germination of this genus is quite trickyand all who have tried would agree with this.Several ways have been tried, and sometimes verydifferent as they are based on different ideas andspeculation on the requirements of this species.Failure has been common. But the method I havebeen using (after more than one year of trials andobservations, reading about habitat conditions,message board interactions, e-mails with manyother palm folk sharing opinions and partialresults) has given me, at last, a fairly good result.

The first consideration is pretreating the seedsbefore sowing. It has been confirmed by many thatletting the seeds dry for some weeks improvesgermination significantly. On this I have addedcold storage for 4 weeks in a refrigerator at 4°C.This has given me excellent results with palms fromtemperate climates (Brahea, Butia), which I havesown by the thousands, and recently with a largebatch of Trithrinax campestris. The cold storageof seeds is a common technique used by growersof other plant families and, indeed, it is neededfor some plants from peculiar habitats (i.e.Sclerocactus and Pediocactus in Cactaceae; manyMesembryanthemaceae-Aizoaceae; some conifers).

After this, the usual soaking in clean water forseveral days has been followed. I have also added agermination stimulator based on NAA, but, nothaving a control batch to compare it to, I cannotexpress an opinion on its efficacy.

At this point, opinion divides. Some growershave used the well-known bag method, which doeswork well for many species, especially the small-seeded and tropical ones. But with Parajubaea, it

has some drawbacks. Firstly, as it is difficult toknow when the radicle will appear, it may growseveral centimeters in the bag and become difficultto pot up due to its odd shape. This makes itnecessary to check the bags frequently, which isnot only quite frustrating for the impatient, butalso a bit dangerous, as the eventual shoots can bedamaged by exploring fingers. But the real problemis that the medium used (peat) allows fungi to growon fruit that remains trapped in the groovedsurfaces of the seeds and this can have devastatingresults on the seed and emerging radicle.

In the spring of 1999, on a first attempt with abatch of 20 P. cocoides, I sowed the seeds directlyinto pots, but even this didn’t give me good results.On this batch, I tried to scarify the seeds withphysical and chemical methods (filing the shellsof 10 and soaking the others in sulfuric acid) butthis was a bad idea because, in the end, the otherunsprouted seeds became mouldy. Not knowingat which stage each seed was, the watering schedulecould not be optimized for both germinated andungerminated seeds. I ended up with only fourplants from this batch and was not satisfied.

I would never consider cracking the shell tosow naked endosperms, as someone suggested withJubaea or Butia yatay, firstly because it’s almostimpossible to crack a P. torallyi shell withoutdamaging the seed, and secondly, the nakedendosperms are easily attacked by fungi. Thismethod could only be used in laboratoryconditions. On the other hand, Nature hasdesigned the seeds so that they will be spread onthe bare ground without killing them and if theseseeds have such a hard shell there must be a valid

15Chamaerops No. 48

16 Chamaerops No. 48

reason. Also, a thick shell doesn’t imply that itis waterproof, and actually the pore from wherethe radicle will push is almost as thin as paper.

So, I decided to try something different.Perhaps inspired from the seed size, I sowed newbatches of P. torallyi v. torallyi, P. torallyi var.microcarpa, P. sunkha and P. cocoides again, usingthe highly successful method I use with cycadseeds. This consists of using polystyrene boxes withlids and that are 20 cm deep (the kind used topack cheese, fish etc.), filled with pure perlite to adepth of 10 cm. The seeds are laid on the surfacesideways with the point down, buried a third ofthe way. Then the perlite is gently watered with afine hose, the lid is put on, and the boxes are puton a shelf 1.90 m above ground in a coldgreenhouse covered with clear plastic and 90%shade cloth. This means that temperatures followthe day-night range, with very little difference. Thecovering doesn’t store much heat at night, so nightindoor temperatures are barely a few degrees aboveoutdoor ones. Conversely, daytime maximumtemperatures can be significantly higher thanoutside the greenhouse.

Here, I put a min/max digital thermometerwith two sensors, and I have recorded thetemperature data inside and outside the boxes.From these data, one thing has become evident.These species like high temperatures to germinate,contrary to the most current advice and despitethe montane habitat of the genus, which wouldsuggest lower temperatures. This could also be thecase for other genera (e.g., Trachycarpus andperhaps Ceroxylon). I have never recorded any signof activity when the maximum temperature wasunder 26°C, and the peak of germination has beenin the range 14°C-35°C. This is easily obtainedfrom late spring to early autumn. In the first triallast year, I achieved the following success rates:11/40 (28%) of P. torallyi var. torallyi, 6/80 (8%)of P. torallyi var. microcarpa,1/30 (3%) of P.sunkha, and 6/10 (60%) of P. cocoides.

When I found no new germination after threeweeks, around late October 2001, I stoppedmisting the seeds. The lids were removed, allowing

the perlite and seeds to dry out totally. The boxeswere left to over-winter. For a period of over onemonth, in January 2002, the minimum nighttimetemperature was constantly in the range of 1°C— 4°C. In early March, the temperatures rose,fitting into the optimal range. So, the perlite waswatered again and the lids put back on the boxes.At the first check, after a week, most of theremaining seeds were germinating: 39/74 of P.torallyi v. microcarpa, and nine more a week later,four P. torallyi v. torallyi and two P. sunkha, andthen a wave of 11 P. sunkha at a later check andstill continuing. I also found four seeds rotten,easily recognized by the white mould growing onthe tip, smelling of rotting coconut (Fig. 1). InAugust 2002, the result was 69 of P. torallyi v.microcarpa, 32 of P. torallyi v. torallyi, and 25 ofP. sunka, which means a rate of over 80%. Notbad indeed!

This process seems to imitate habitatconditions rather well—a dry, cool winter and amoist, hot summer—which suits the seeds.Another consideration is that, in the northernhemisphere, we usually get fresh seeds around latewinter, while in habitat it is the opposite season. Ibelieve that the poor results I got initially resultedbecause the seeds should have quite a long periodof rest, helpful to induce/remove some chemicalsto trigger germination.

The box technique means not having to botherwatering the seeds. I just mist them with a handsprayer when they are dry (the shells turn fromdark to light brown). There is no risk of under- oroverwatering because, with the lid on, theevaporation is minimal and moisture is heldconstant. Also, no problem occurs if one overlooksweekly checking for sprouts, as I often do. Theradicle grows straight down in the moist yet porousperlite, and no harm will be done pulling up thegerminated seed. When the radicle is 4-5 cm long,it’s time to pot it up. I use tall, square pots(10x10x20 cm) filled with a mix of peat/sand/perlite in equal parts. A bit of care is needed forthe first watering, as they are sensitive to rot. Thefirst leaf will appear some weeks later (Fig. 2).

17Chamaerops No. 48

It’s not uncommon to find seeds with twoembryos, especially with the variety torallyi, andthis feature has been observed many times inrelated genera (Butia, Syagrus, Jubaea, Acrocomia,Attalea). Leaving them to grow together could givean unusual effect in years to come (Fig. 3), butany attempt to divide them after the germinationstage would be fatal for the palm! An easy trickcan be used to get two independent plants. Oncethe radicles are of the right length, I put the seedon the edge of two pots, joined side by side withheavy tape, allowing each root to go in its ownpot. A small square pot of 7cm, with the bottomcut off, is placed over the two pots and is insertedwith the help of two notches. The remaining spaceis filled with the mix. This is to prevent thehypocotyls from drying out or being damagedaccidentally. After about a year the seed will bespent and the two pots can be separated. And then& two plants for the price of one. Voilá!

All Parajubaea species need to be grown in fullsun outdoors from the first leaf stage, at leastduring the warmest months, as they resentgreenhouse conditions (lack of air movement andhigh level of humidity). Otherwise, they developweak leaves with yellow stripes, which bend anddie slowly. This also indicates the adaptability ofthis genus to subtropical areas with moist summers.While the ultimate cold hardiness of the severalspecies is still to be well tested, as there aren’t oldspecimens in cultivation outside habitat,Parajubaea are surely some of the most promisingnew palms for temperate climates.

Reproduced with permission by the authorfrom the Palm & Cycad Societies of Florida, Inc.web site http://www.plantapalm.com/. Have a lookat their award-winning Virtual Palm Encyclopediafor a wealth of information on palms and cycads.

to lack of moisture, though why this shouldbe so I have no idea.

In its first year (2001), the M. sikkimensisthrew up four side-shoots. Since then, it hasproduced one or two more that have died off atless than 80 mm in height. As it lost one to rot lastSpring, it now has four pseudo-stems. It appearsto me that it will not produce any more until theoriginal shoot flowers. Last Winter, I have wrappedall three Bananas again, after mulching the bases.

The only other plants I protected withhorticultural fleece were two Brugmansias (B.suaveolens and B. 'Charles Grimaldi') that I amexperimenting with by planting in the ground (Ikeep small rooted plants indoors as 'cover'). In,2000/01, I wrapped my Phoenix canariensis andYucca elephantipes, but they seemed to cope easily,unprotected, with -4∫ C in 2001/02 and with -5∫C. last Winter, so I shan't bother unless we have atruly lethal Winter. The Phoenix is about 10 yearsold, but has been in the ground for only 3 yearsand is about 1.5 m tall. The Yucca is a substantialplant, also about 10 years old, with 6 or 7 stemsand is about 2.4 m tall. All of my other Palms(except the inevitable Trachycarpus fortunei, whichis making slow progress in a shady spot) are fartoo small to plant out.

...continued from page 20

M o r e o n M u s a

18 Chamaerops No. 48

N e w P a l m B o o k A v a i l a b l e

A n E n c y c l o p e d i a o fC u l t i v a t e d P a l m sBy Robert Lee Riffle and Paul Craft

Co-written by the author of the award-winningThe Tropical Look, An Encyclopedia of CultivatedPalms offers a definitive account of palms that maybe grown in the garden and landscape. Becausepalms are often underutilized as a result of theirunfamiliarity---even to tropical gardeners---RobertLee Riffle and Paul Craft have exhaustivelydocumented every genus in the palm family.Approximately 890 species are described in detail,including cold hardiness, water needs, height, andany special requirements. No gardener orlandscaper who reads this book should ever againlose a palm solely because of lack of horticulturalinformation.

Generously illustrated with more than 900photos, An Encyclopedia of Cultivated Palms isas valuable as an identification guide as it is apractical handbook. The volume even containsphotos of several palm species that have neverbefore appeared in a general encyclopedia.Interesting snippets of history, ethnobotany, andbiology inform the text and make this a livelycatalog of these remarkable plants. As well as all ofthe tropical and subtropical palms, theencyclopedia includes many species that canwithstand freezing; thus it is applicable for areaswhere average low temperatures do not drop below5ºF (-15ºC).

Many features of the book add to its usefulnessfor the amateur or professional grower. Extensivelandscape lists group together palms with specialcharacteristics, such as drought tolerance, salttolerance, and slow growth, to name a few. Aunique appendix with notes on germinating seedof selected palms will prove invaluable to gardeners

and nursery professionals who wish to grow palmsfrom seed. In all, An Encyclopedia of CultivatedPalms offers a wealth of information tohorticulturists at every level of experience.

528 pp, 929 color photos, 1 b/w photo, 2 line drawings, 8 1/2 x

11", hardcover, ISBN: 0-88192-558-6, available now via the EPS

webite at:

http://www.palmsociety.org/public/english/booklist/palms.shtml

P a l m e n i n M i t t e l e u r o p a .A n l e i t u n g z u m e r f o l g -r e i c h e n A u s p f l a n z e nu n d Ü b e r w i n t e r n .

Mario Stähler stellt in seinem Buch 24Palmenarten vor, die in Mitteleuropa ausgepflanztwerden können. Eine eingehende Betrachtung desKlimas in Deutschland, Österreich und derSchweiz gibt Aufschluss darüber, welche Art woam besten wachsen kann. Praktische Hinweise zumrichtigen Standort, zur Bodenbeschaffenheit,Düngung, Wässerung, zu Krankheiten undSchädlingen und vor allem zur sicheren underfolgreichen Überwinterung im Freien machendieses Buch zu einem unentbehrlichen Ratgeber.

Klappenbroschur, 72 Seiten, 18 Farbfotos, 8 s/w Abbildungen

21 x 14,5 cm

Verlag: The European Palm Society

EUR 15,20 (zzgl. Versandkosten EUR 2,90)Dieses Buch kann bestellt werden bei:The European Palm SocietyTobias W. SpannerTizianstr. 4480638 München (Germany)(+49) 089 1577902

19Chamaerops No. 48

W e b U p d a t e

For all those of our members, who have nothad the chance yet to visit our web site atwww.palmsociety.org or who are still undecided ifthey should spend the extra £5 per year* for theon-line membership here is a brief overview ofwhat happened on the web site of the EuropeanPalm Society since our last report in Chamaeropsissue #45:

There are now 300 on-line members, 70 moresince issue #45.

Visitor numbers have increased to 5000 eachmonth. Many of them are non-members browsingthe public section which contains one article fromeach Chamaerops issue - 48 free articles. Have alook at their comments in the guestbook! There isalso a Book List with recommended books, a smallshop for Chamaerops back issues and many usefullinks to other interesting web sites.

For just £5 (Euro 7.50) per year you get accessto the Chamaerops archive - now containing all371 articles from all previously publishedChamaerops issues, including all pictures! You canmeet other EPS members in our lively discussionforum: 14,000 postings! Try to catch up with NigelKembrey who has posted more than 2000messages!

And in the members shop you can buy backissues at only £2 (Euro 3) per issue (but who wantsto buy back issues anyway if you can search themby keywords on-line?)

w w w . p a l m s o c i e t y . o r g

* Yes, it's just £5 (Euro 7.50) extra per year toget full access to the web site of the European PalmSociety. You can join on-line athttp://www.palmsociety.org/join/english1.shtml

20 Chamaerops No. 48

Poncirus trifoliata with ripe fruit, growing in SoutheasternGermany. Article see page 12. Photo: Tobias W. Spanner

M o r e o n M u s a

By David Matzdorf, London, UK

I promised to send progress reports on growingthis plant and I have not strictly kept my word.My Musa sikkimensis was planted out inSeptember 2000 as a very small second-year plant,0.7 m tall. Summer 2002 was a great success, withlush, shiny growth up to 3.6 m. That Summer wasunusually calm and there was good balance of sunand rain.

Then in August 2002, something strikinghappened. There was an un-seasonal gale. I haveread on more than one occasion that M.sikkimensis is supposed to be more wind-resistantthan M. basjoo. This is true, insofar as the leaveshave a thicker, waxier texture and are less prone tobecome shredded as soon as there is more than amild breeze.

However, I have discovered that there is adownside to this characteristic. On two occasions,first in August 2002 and then again in June 2003,a sharp gust of wind has completely snapped offan entire pseudo-stem. I have never know this tohappen to M. basjoo and I can only theorise thatthis is precisely because the tendency for M.basjoo's leaves to become shredded reduces theoverall resistance of the plant. M. sikkimensis doesnot do this and the result was major damage and asetback to the entire plant. In August 2002 a sidepseudo-stem snapped off at 0.6 m height in a majorgale and then, in June 2003, the original mainpseudo-stem was reduced from 2.4 m to about 1.0m in a local, rather freakish, sharp afternoon squall.Last Autumn, in preparation for the possibility offurther gales, I have removed approximately halfof the leaves before the cold required me to do so.

In Winter 2002/03, I did the usual thing andwrapped the pseudo-stems in 2 - 3 layers ofhorticultural fleece. As usual, there was no frost

damage at all, despite two weeklong freezes andthe lowest temperatures (-5∫ C) since I moved herein June 2000. However, when Spring arrived, oneof the five pseudo-stems failed to make growthand proved to have a localised rot at the base. Iremoved it and watered the plant with Murphy'sTraditional Copper Fungicide, which seems tohave dealt with the problem.

The main problem for both of my largeBananas this year has been protracted drought.Unlike M. basjoo and M. sikkimensis, my youngplant of Musella lasiocarpa (planted out in June2003) seems to have been relatively unaffected,although it completely stopped growing for about3 weeks in response to the record-breaking heatwave in August. Despite applying 10

litres of water (with a balanced soluble fertiliser)to each plant once or twice a week, I simplycouldn't keep up with the fact that the soil hadbecome desiccated to a very substantial depth. Idon't water with a hose for water-conservationreasons. So last year, watering became an exercisein keeping the Bananas alive.

The M. basjoo is in a shadier, more shelteredspot with less competition and fared better,although it made conspicuously less growth thanin 2002. The growth of M. sikkimensis wasdramatically reduced and most of the leavesemerged with large brown patches as they unfurled.My M. sikkimensis generally has purple newgrowth, especially in warm conditions, althoughthe new leaves become green after they open.Interestingly, this year, the plant showed no signof purple throughout the long dry period, which,in London, lasted from mid-February until lateOctober. I have to conclude that this was a response

Continued on page 17...

21Chamaerops No. 48

22 Chamaerops No. 48

23Chamaerops No. 48

S h o p

Chamaerops back-issues# 47 £2 / EUR 3.00# 46 Spring 2002 £2 / EUR 3.00# 46 Spring 2002 £2 / EUR 3.00# 46 Spring 2002 £2 / EUR 3.00# 45 Winter 2001/2002 £2 / EUR 3.00# 43-44 Summer 2001 £4 / EUR 6.00# 42 Spring 2001 £2 / EUR 3.00# 41 Winter 2000 £2 / EUR 3.00# 40 Autumn 2000 £2 / EUR 3.00# 39 Summer 2000 £2 / EUR 3.00# 38 Spring 2000 £2 / EUR 3.00# 37 Winter 1999/2000 £2 / EUR 3.00# 35-36 Summer 1999 £4 / EUR 6.00# 34 Spring 1999 £2 / EUR 3.00# 33 Winter 1998/99 £2 / EUR 3.00# 32 Autumn 1998 £2 / EUR 3.00# 31 Summer 1998 £2 / EUR 3.00# 30 Spring 1998 £2 / EUR 3.00# 29 Winter 1997/98 £2 / EUR 3.00# 28 Autumn 1997 £2 / EUR 3.00# 27 Summer 1997 £2 / EUR 3.00# 26 Spring 1997 £2 / EUR 3.00# 25 Winter 1996/97 £2 / EUR 3.00# 24 Autumn 1996 £2 / EUR 3.00# 23 Summer 1996 £2 / EUR 3.00Any 10 for just £15 / EUR 22.00

EPS BadgeChrome with colour printing £4 / EUR 6.00

Please send your orders toTony King34, Keats AvenueRomford, Essex RM3 7ARUnited Kingdom

All prices include delivery to anywhere in theworld. Payable by credit card (Visa or Mastercard),cheque, or money order.

P l e a s e s e n d l e t t e r s ,a r t i c l e s a n d p i c t u r e s t o

The European Palm Societyc/o Tobias W. SpannerTizianstr. 4480638 MünchenGermanyE-mail: mail@palmsociety.org

L e t t e r s

D e a r E d i t o r ,

in January my wife and I were fortunate tomake an all too short journey betweenJohannesburg and Durban, South Africa,including the northeast corner of Lesotho. Therange of vegetation throughout was immense andexciting, but I write to recommend to visitors theDurban Botanical Garden. Whilst not huge, beingbased on the 50 acres purchased in the mid 1800s,here is a superb collection of plants, especiallypalms and cycads.

A booklet entitled The Palm Collection of theDurban Botanic Gardens (Ann Lamberk R.40) isa good introduction. The chapter on cultivationis very informative. One aspect noted is that therecent advice to plant our palms deeply iscontradicted: “Palms do not like to be sunk deeplyinto the ground or have soil piled up around thestem”. Perhaps other local cultivation parametersinfluence this advice?

One of the many palms to attract attention wasthe native Lala palm, Hyphaene coriacea (syn. H.natalensis), seen in the wild and in the Garden. Itis said that they can withstand —5∞C (23∞F)temperatures.

Best Wishes, Rob Senior, The Old Rectory,Green Lane, Marazion, Cornwall TR17 OHQ

w w w . p a l m s o c i e t y . o r g