RHS Plant Trials and AssessmentsRHS Plant Trials and Assessments

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CaryopterisDiana Millerformer Keeper of the RHS Herbarium Wisley

Supplementary to RHS Trials and Awards: Number 2December 2007

CaryopterisDiana Millerformer Keeper of the RHS Herbarium Wisley

Supplementary to RHS Trials and Awards: Number 2December 2007

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Caryopteris are very useful, autumn-flowering shrubsespecially appropriate for the smaller garden as they rarelyexceed a metre in height and spread and are tolerant ofmost garden soils if grown in a well-drained, sunnyposition. In colder areas the top growth may be damagedby frosts so pruning in spring will encourage theproduction of healthy new growth from lower down. Theycan be used in mixed or shrub borders or even as containerplants. Their greyish foliage is attractive throughout theseason and the flowers, usually a shade of blue, form inlate summer and early autumn when there is little else ofthis colour in flower. Even the dark or greeny blue, inflatedfruiting heads can be a feature long after the flowers arefinished. Blue, pink and white-flowered forms of C. incanaare also grown for the cut flower market, especially inNorth America and the Netherlands.

The Woody Plant Trials Subcommittee decided in 1996 toconduct a trial of Caryopteris because there were a numberof new cultivars coming into the market and the confusionconcerning the nomenclature of some of the oldercultivars.

Objectives:� To compare old and new cultivars and nominate the

most distinctive and outstanding for the RHS Awardof Garden Merit

� To establish the hardiness of new introductions

� To confirm correct nomenclature

� To prepare a collection of pressed herbariumspecimens and photographic images, together withdetailed descriptions, as a permanent record

EntriesThree plants of each of the 41 entries in the trial weresubmitted by individuals, nurseries and the National PlantCollections ® holder.

CultivationThe entries were planted in April 1998, 1m apart in lightsandy soil with a pH of 6.5 on the Trial Ground in WisleyVillage. The plants were irrigated only to aid establishment.All plants established and grew well in the first year.

In March 1999 a pruning regime was undertaken, with oneplant of each entry being cut back to two buds, one plantcut half way down and the third plant given a light prune.There were hard frosts on the nights of 13 and 14 April(-3.8˚C and -3.3˚C consecutively) and by June 1999 it wasevident that many of the plants had died. However, nopattern of susceptibility was evident from the differentpruning regimes. It was decided to re-propagate or, wherenecessary, ask for fresh stock. It was noted that Caryopteriscuttings root best in a loam mix. The cuttings in 9cm potswere potted on into 1 litre pots in March 2000.

The trial was replanted on 8 June 2000. In August it wasnoted that the ground at the trials site was dusty and poor,conditions that generally suit these plants. The trial wasthen seriously affected by flooding in November 2000,which caused the death of the majority of the plants, and adecision was made in 2001 to abandon the trial. Peter Catt,the owner of Liss Forest Nursery, agreed to build up thecollection again at his nursery. The Committee, using theirnotes from the Wisley trial, assessed many of the originalentries at Liss Forest Nursery in 2006 and in 2007 and wereable to complete the original objectives of the trial.

SummaryIt was noted that Caryopteris require a sunny site; do bestin free-draining soils; are not sensitive to pH and respondwell to being lightly pruned after flowering then cut backin March.

Some cultivars were noted for a particular quality e.g.'Heavenly Baby’ for its compact habit; ‘Longwood Blue’ asa good later flowering cultivar; ‘First Choice’ for havingone of the darkest blue flowers and ‘Blue Cascade’ for itsweeping habit.

Caryopteris

RHS Plant Trials and Assessments

Front cover: C. � clandonensis HINT OF GOLD (‘Lisaura’)

Left: C. � clandonensis ‘Kew Blue’

Right: C. � clandonensis ‘Heavenly Baby’

Photos: Wendy Wesley

3Caryopteris

Caryopteris � clandonensis AGM(H3-4)2002‘First Choice’ re-confirmed

Caryopteris � clandonensis AGM(H3-4)2007‘Heavenly Baby’

Caryopteris � clandonensis AGM(H3-4)2007HINT OF GOLD (‘Lisaura’)

Caryopteris � clandonensis AGM(H3-4)2007‘Summer Sorbet’

Caryopteris � clandonensis AGM(H3-4)2002‘Worcester Gold’ re-confirmed

Caryopteris � clandonensis AGM (H4) 2002‘Arthur Simmonds’ see note on page 6

RHS hardiness ratings: (H3-4) hardy outsidein most regions

The Award of Garden MeritThe AGM is only awarded to plants that are:

� Excellent for garden decoration

� Available from nurseries

� Reasonably resistant to pests and diseases

� Of good constitution

� Essentially stable in form and colour

� Reasonably easy to grow

Award of Garden Merit

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Origins of garden Caryopteris

RHS Plant Trials and Assessments

The genus CaryopterisCaryopteris is a genus of perennials and shrubs native toAsia and particularly well represented in China, mostlyfound on dry mountain slopes. Caryopteris can be difficultto differentiate from one another, so estimates of thenumber of species vary. Recent treatments accept 16species in Caryopteris, but few of these are widely grown ingardens and cultivars of the shrubby species are almost allselections of C. incana or its hybrid C. � clandonensis.

In 1988 when the NCCPG and the RHS Herbariumexhibited a collection of Caryopteris there were only 5named cultivars available in Britain but two decades laterthe 2007-2008 edition of RHS Plant Finder listed 20cultivars of shrubby Caryopteris. New cultivars are stillbeing developed and as the breeding potential of so manyspecies is yet to be tried there are likely to be many moreintroductions in the future.

C. incanaThis is a very variable species which is found growing wildover a large area of China, Japan, Taiwan and Korea. It wasintroduced into the UK from Canton in China by RobertFortune in about 1844, when it was treated as a greenhouseplant. About forty years later Maries collected material fromJapan for Veitch’s Nursery which proved to be much hardier.

C. incana is a small, bushy, deciduous woody shrubreaching about 1.5m tall with ovate, regularly toothed,leaves, green above and greyer beneath. The tiny flowersare 5-lobed with a larger fringed lower lip and 4 protrudingstamens, formed in dense axillary clusters on stalks in theaxils of the upper leaves. The calyx becomes inflated afterthe flowers are pollinated and the seeds develop. Theflowers of the first introductions were blue, but plants withpink and white flowers can be found in the wild. White-flowered forms have been named C. incana f. candida andpink flowered ones C. incana f. superba both of which areusually considered to be more tender. There are also largerleaved forms most of which are collected from loweraltitudes and which are consequently less hardy. Thesecollections from different locations show considerablevariation in morphology and hardiness and this variationhas given rise to a certain amount of confusion innomenclature.

C. incana C. mongholica C. �� clandonensis

C. incana C. mongholica C. �� clandonensis

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C. tangutica Plants received as C. tangutica were grown in the Trial, butthe results of a molecular project carried out at ReadingUniversity, suggest they were a form of C. incana. C. tangutica are robust plants, apparently quite hardy witha stiff, upright, little-branched habit but in othermorphological characteristics similar to normal C. incana.

C. mongholica A native of Mongolia and western China, this species wasfirst introduced into France after Bunge had discoveredand named it in 1833 then it was lost. Père Davidreintroduced it from southern Mongolia in 1866.

It is a smaller plant than C. incana reaching about 75cm inheight with linear to lanceolate, untoothed grey-greenleaves. The darker blue flowers with a fringed 2-lobedlower lip, are formed in a loose branching inflorescenceearlier than those of C. incana. Arthur Simmonds, a formerSecretary to the RHS, noted that it was quite hardy exceptin one exceptional frost. This species is almost certainlysensitive to the humid winter conditions found in the UK,although it would probably tolerate the cold if kept dry. Itis not in general cultivation in the UK and material of thetrue plant proved exceedingly difficult to obtain, mostplants under this name being C. incana or the hybrid.

C. �� clandonensisThis hybrid was first discovered in the early 1930s byArthur Simmonds, then Secretary of the RHS, growing as aseedling in his garden at West Clandon, Surrey. We knowhe considered the plant to include C. mongholica in itsparentage because of a handwritten addendum to a letterwritten by Simmonds to W. J. Bean in 1943 in which hestates, ‘The original plant of clandonensis still exists and itwas undamaged by the winter which killed its mother –mongolica [sic].’ The parentage C. incana � C. mongholicawas finally confirmed for C. � clandonensis by molecularwork sponsored by the RHS and carried out at ReadingUniversity (Beharrell & Culham, 2006).

It is a bushy shrub that grows to about 1m in height withdull green, narrow-elliptic, irregularly toothed leaves, palerbelow. The flowers, in looser clusters than those of C.incana, are blue but the various cultivars range in colourfrom pale to deep blue. The cultivars seed freely and anumber of hardy named cultivars have become verypopular autumn-flowering plants. However, a profusion ofseedlings has resulted in confusion concerning the identityof some of the earlier cultivars and to ensure thecontinuation of the true cultivars, propagation must bevegetative.

Other species Caryopteris divaricata is herbaceous

Caryopteris forrestii has greenish yellow flowers

Caryopteris terniflora has pink flowers in spring and is notvery hardy (was sent to Trial as C. odorata, but did notsurvive)

A painting of C. � clandonensis byDorothy Martin from the specimen thatwas shown by A Simmonds Esq. ofHarmsworths, West Clandon, Surrey andwhich received an Award of Merit forexhibition from Floral Committee A on12 September 1933.

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Cultivars of C. � clandonensis

C. � clandonensis ‘ArthurSimmonds’ A bushy plant with grey-green leaves with a few teethtowards the apex. Flowersmid blue. Blue-tinged greenfruiting calyx. This is thename given to the originalclone of C. � clandonensisraised by Arthur Simmonds ofWest Clandon, Surrey inabout 1930. Probably nolonger in cultivation. Plantsgrown under this name noware similar to ‘Heavenly Blue’.

C. � clandonensis ‘BlauerSpatz’ An erect but rather shortplant with red stems andgreen, broad-elliptic leaveswith many large conspicuousteeth. Flowers deep blue.Dark blue fruiting calyxturning greeny blue. Selectedby Dr Pirc, HBLVA fürGartenbau, Wien-Schönbrunn, Austria.

C. � clandonensis ‘BlueMist’A bushy, fairly upright plantwith broad-elliptic, grey-green leaves, toothed towardsthe apex. Flowers over a longseason, pale powder blue.Greeny blue fruiting calyx.Raised and introduced byWayside Gardens, Ohio inUSA in about 1942.

C. � clandonensis ‘DarkKnight’ An erect plant with darkreddish stems and grey-greenleaves with a few large teeth.Flowers late, dark blue.Fruiting calyx grey-blue.Raised in USA. Very similar to‘Pershore’, a plant bought byPershore College ofHorticulture from Hollandlabelled ‘Heavenly Blue’ butconsidered to be quitedistinct from that cultivar.Introduced by the College inthe early 1990’s.

C. � clandonensis‘Ferndown’ A short but erect plant withnarrow, dark green, slightlyglossy leaves with very fewteeth. Flowers, dark blue with aslightly paler lip produced verylate in the season. The calyxbecomes dark blue but doesnot inflate in fruit and thereare few fertile seeds. Raised byStewarts Nursery in Ferndown,Dorset before 1958 from aseedling of an unknown formof C. � clandonensis. Thiscultivar appears to tendtowards C. mongholica in itssmaller size and narrow, rarelytoothed leaves.

C. � clandonensis ‘FirstChoice’ A compact, erect plant withdark reddish stems and greenleaves with a few small teethin upper half. Flowers a richer,darker blue than other cultivarswith a tiny white centreformed in a close flower head.The fruiting calyx is very darkblue. The leaves have a purplishtint in winter. Selected fromseedlings raised by Peter Cattand introduced by Liss ForestNurseries in 1997. Close to‘Kew Blue’ but with a slightlylonger flowering season, and adenser habit which makes thefoliage appear darker.

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C. � clandonensis‘Gold Giant’ A strong–growing, spreadingplant with large, long,irregularly toothed goldenfoliage which retains itscolour well into the autumn.The mid blue flowers areslightly darker and later thanthose of ‘Worcester Gold’.Fruiting calyx is jade green.Selected from seedlings raisedby Peter Catt and introducedby Liss Forest Nurseries in2007.

C. � clandonensis GRAND BLEU(‘Inoveris’) **An erect plant with reddishstems and dark green leaveswith a few large roundedteeth. The foliage appearsrather sombre. Flowers a richdark blue. Blue fruiting calyx.This cultivar does not setseed. Raised by INRA andintroduced by André Briantin France in 1997.

C. � clandonensis ‘HeavenlyBaby’ A dwarf plant with very smallsilvery grey leaves and small,sharp teeth. Flowers paleblue. Pale grey-green fruitingcalyx. Seedling found byRachel Thompson in herSurrey garden and introducedby Liss Forest Nurseries in2001.

C. � clandonensis‘Heavenly Blue’ A bushy to erect plant withreddish stems and rather large,grey-green leaves with a fewteeth near the apex. Flowersmid to dark blue. Very largeturquoise to pale blue fruitingcalyx. Raised in WaysideGardens, Ohio, USA in 1953 .Similar to the original ‘ArthurSimmonds’. It was recorded in1963 that the cultivar hasbeen sold as seed by at leastone Canadian Nursery andalthough many plants are soldunder this name in the UK, itis not certain that they areidentical to the original raisedin the USA.

C. � clandonensisHINT OF GOLD ('Lisaura') An upright growing plantwith regularly toothed, large,broad, gold-coloured leaves.The flowers arranged in atight inflorescence aroundthe stems are a rich mid blue.Fruiting calyx is dark, greenyblue. Although a hybrid, thiscultivar is very close to C. incana in flower andfoliage. Selected fromseedlings raised by Peter Cattand introduced by Liss ForestNurseries in 2007.

C. � clandonensis‘Kew Blue’ An erect, rather short plantwith reddish stems andnarrow green leaves with afew teeth. Flowers a darkblue. Very dark, almost navyblue fruiting calyx. Selectedat Kew Gardens in 1945 as aseedling of ‘ArthurSimmonds’ for its darkerflowers. Closest to ‘FirstChoice’ but with a slightlyshorter flowering season andpossibly slightly less hardy.

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Cultivars of C. × clandonensis

RHS Plant Trials and Assessments

C. � clandonensis‘Longwood Blue’A large, vigorous, ratherspreading cultivar withsilvery, grey-green, narrowleaves that have a few largeteeth along the margin.Stems reddish brown. Flowersmid blue and lips with anarrow white fringe whenviewed though a lens,produced late in the season.Fruiting calyx blue-tinged.Selected in 1981 as a large,vigorous seedling byLongwood Gardens, USA anddistributed by WaysideGardens, USA in 1987.

C. � clandonensis ‘LouisCornuz’ A tall plant with reddish stemsand a rather lax habit andlanceolate, often untoothed,glossy, green leaves. Largeflower heads of mid blue. Bluefruiting calyx. Raised inSwitzerland and introducedinto the UK in 1999. Thiscultivar appears to be close toC. mongholica. It is reputed tobe hardier than many.

C. � clandonensis‘Moody Blue’ A rather lax plant with palereddish stems and small,narrow ovate, green leaves,deeply toothed towards theapex with a pale creammargin. Flowers pale blue.Deeply lobed pale blue togreen, slightly inflatedfruiting calyx. Raised inIreland by Kieran Dunne andintroduced by Liss ForestNurseries in 2003. The leavestend to burn if grown in fullsun.

C. � clandonensis ‘SummerSorbet’ (syn. ‘Dyraisey’) A bushy plant with elliptic,few toothed leaves with anirregular yellow margin anddark stems. Flowers pale blue.Pale blue tinged fruitingcalyx. Found as a sport andintroduced by Peter van Delftof West End Nurseries, Devonin about 2004.

C. � clandonensis ‘Thetis’(syn. ‘Steinthe’) In the trial this cultivarseemed to be almost identicalto ‘Dark Knight’ although theflowers were produced a littleearlier and showed a slightlymore mauve tint. Raised bySteinegger in Germany inabout 2002.

C. � clandonensis‘Worcester Gold’ A bushy plant distinguishedby its bright yellow foliage insummer which is slightlypaler at flowering time.Flowers mid blue with alarger lip than some othercultivars. Fruiting calyx jadegreen. Selected in St JohnsNurseries in Worcester in thelate 1970s. This cultivar needsto be grown in the sun forthe best yellow leaf colour.

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Cultivars of C. incana

C. incana ‘Autumn Pink’A bushy plant with broad ovate, green,toothed leaves. Flowers very late, palepink, with a green fruiting calyx.Introduced into UK gardens in about2000. Not very hardy.

C. incana ‘Blue Cascade’* A strong-growing plant with long,cascading branches, often trailing onthe ground, with ovate, toothed greenleaves. Flowers pale blue in dense,many-flowered clusters with green-blue tinged fruiting calyx. This plant'sweeping habit can be displayed to besteffect if grown over a wall, on a bankor in a large container. The origin of‘Blue Cascade’ is not clear, but it maybe derived from an American cultivarnamed ‘Blue Billows’ which wascollected by the Longwood Gardens(Pennsylvania, USA) expedition toKorea in 1966. It was distributed toWisley in 1976 under the accessionnumber 69860 and was named in 1977by Dr D G Huttleston of LongwoodGardens. Images of ‘Blue Billows’ sentfrom Longwood suggest the two plantsare not the same clone for while ‘BlueBillows’ shares the same weeping habitas ‘Blue Cascade’ it appears to have lesslobed leaves and a less silveryunderside. It is suspected that ‘BlueCascade’ may be a descendent of theAmerican introduction.

C. incana ‘Jason’ (syn. SUNSHINE BLUE)* An upright bushy plant with smallyellow leaves, bright yellow in latespring but a greener yellow by latesummer. Flowers pale to mid blue.Greeny blue, small fruiting calyx.Raised by Peter Chapman andintroduced by Notcutts Nurseries inabout 2002.

Trial in the NetherlandsThe Applied Plant Research station at Boskoop incooperation with the Royal Boskoop HorticulturalSociety undertook a trial of Caryopteris (reportedin Dendroflora Nr 43 2006).

The results were:

*** Excellent

Caryopteris x clandonensis'First Choice'

** Very good

Caryopteris x clandonensis‘Heavenly Blue’

Caryopteris x clandonensis‘Inoveris’ GRAND BLEU

Caryopteris x clandonensis'Summer Sorbet’

* Good

C. incana ‘Blue Cascade’

C. incana ‘Jason’ SUNSHINE BLUE

Nomenclatural standard of Caryopteris incana(Thunb. Ex Houtt.) Miq. ‘Blue Cascade’

This is the nomenclatural standard for Caryopterisincana ‘Blue Cascade’ which forms a permanentrecord of the distinguishing characters of thecultivar ‘Blue Cascade’, which is deposited in theRHS Herbarium (WSY).

The RHS Herbarium is leading an internationalinitiative to prepare specimens of new cultivars asthey are introduced. This will help to reduce thenumbers of incorrectly named plants. Many trialsconducted by the RHS provide a good source ofstandard specimens.

10 RHS Plant Trials and Assessments

From left to right:

1 ‘Gold Charm’

2 ‘Gold Giant’

3 ‘Blue Cascade’

4 ‘Worcester Gold’

5 ‘Dark Knight’

6 ‘Hint of Gold’

7 ‘Louis Cornuz’

8 ‘Pershore’

9 ‘Kew Blue’

10 ‘Blauer Spatz’

11 ‘Heavenly Baby’

12 ‘First Choice’

13 ‘Ferndown’

14 ‘Summer Sorbet’

15 ‘Thetis’

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11Caryopteris

Senders of plants to the trial:Avonbank Nurseries, Pershore & Hindlip College, Pershore,

WR10 3JP

www.warkscol.ac.uk/pershore/avonbank/

Bridgemere Nurseries, Nantwich,Cheshire,CW5 7QBwww.bridgemere.co.uk

The Beth Chatto Gardens Ltd, Colchester, CO7 7DBwww.bethchatto.co.uk

Darby Nursery Stock Ltd, Methwold, Thetford, IP26 4PW

Darthuizer Boomkwekerijen BV, 3956 ZR Leersum, Hollandwww.darthuizer.nl

Hopleys Plants Ltd, Much Hadham, Hertfordshire, SG10 6BU www.hopleys.co.uk

Jackdaws' Field Nursery, Maplehurst, West Sussex, RH13 6LL www.jackdawsfield.co.uk

Liss Forest Nursery Ltd, Greatham, Liss, Hampshire, GU33 6HA

Notcutts Nurseries, Woodbridge, Suffolk IP12 4AFwww.notcutts.co.uk

Perryhill Nurseries, Hartfield, Sussex TN7 4JPwww.perryhillnurseries.co.uk

Pleasant View Nursery, Newton Abbott, TQ12 6DG

National Plant Collections ® Bristol Zoo Gardens, Clifton, Bristol, Somerset BS8 3HA(www.bristolzoo.org.uk)

AcknowledgementsThe RHS are indebted to Peter Catt, plantsman andnurseryman, owner of Liss Forest Wholesale Nursery Treesand Shrubs, who for the past four years has been growingthe Caryopteris for the Woody Plant Trials Subcommittee toassess and compare. Peter Catt also has some promisingnew cultivars from his ongoing Caryopteris breedingprogramme.

Particular thanks are also due to:

� James Armitage (Botanist) for researching the currentstatus of the cultivars mentioned in this bulletin, inparticular ‘Blue Cascade’, and for editing and proof-reading.

� Wendy Wesley for all the photographs in this bulletin,unless otherwise stated;

� Barry Phillips (Herbarium Technician) for collectingand describing entries for the herbarium;

� Susan Grayer (Herbarium Researcher) for creating thestandard specimens;

� Chrissie Ferriroli (Trials Recorder) for recording thetrial and Wendy Wesley (Trials Officer) for recordingthe assessment and collating all the information;

� RHS Floral Trials curatorial staff, headed by JimEngland (Trials Superintendent) for planting andmaintaining the trial;

� Eddie Mole of Bristol Zoo Gardens (NCCPG holder);

� All other senders of plants to the trial without whomthe trial could not have taken place

Further readingBeharrell, N. and Culham, A. (2006) The Origin ofCaryopteris � clandonensis and its cultivars. The Plantsman(NS) (5): 192-197.

Hoffman, M.H.A. (2006) Caryopteris – sortimentsonerzoeken keuringsrapport. Dendroflora 43 : 65-79.

Caryopteris seedlings

The Royal Horticultural SocietyThe RHS is the UK’s leading gardening charity dedicated toadvancing horticulture and promoting good gardening. Itscharitable work includes providing expert advice andinformation, advancing horticulture, training the nextgeneration of gardeners, helping school children learnabout plants, and conducting research into plants, pestsand environmental issues affecting gardeners. The RHSAGM plant trial scheme is an important part of this work.The RHS receives no government grants and for everypound received from members’ subscriptions we need toraise more than twice as much again to fund our charitablework. We also rely on donations and sponsorship tosupplement income from our garden operations, flowershows, shops and plant centres.

RHS Plant TrialsWith so many different types of gardener and so manydifferent cultivars available to them in each group ofplants, it is important that a system of recommendation isin place to help with selection at point of sale. Theserecommendations must be clear and reliable to ensure thatof the thousands of plants available in the UK, aproportion are identified as excellent garden plants. TheRHS provides this information through its extensiveprogramme of plant trials held at RHS gardens in the UK.The RHS Award of Garden Merit indicates whichcultivars are best for general garden use.

RHS plant trials serve the professional gardener who wantsto know the range of plants available, including the latestbreeding and selection programmes, with their distinctivecharacteristics and provenance. They also serve theamateur who wants to know which plants will grow andperform well in a particular garden situation.

The RHS has an unrivalled resource of knowledge andexpertise and is therefore best placed to conduct planttrials for the UK gardening market.

RHS Herbarium (WSY)The RHS Herbarium is the largest and most active of asmall number in the world dedicated to preservinghorticultural plants. The collection has c. 70,000specimens, c. 35,000 photographic images and 3,500paintings. This is a valuable archive consulted daily by RHSbotanists and outside researchers.

RHS BulletinsBegonia Rex Cultorum Group: December 2006Canna: September 2003Daisies (yellow perennial): September 2004Delphinium: June 2004Fuchsia (hardy): December 2005Geranium (hardy) Stage 1: June 2005Geranium (hardy) Stage 2: June 2006Geranium (hardy) Stage 3: June 2007Hyacinthaceae (little blue bulbs): September 2005Iris (bearded): May 2007Lavenders (hardy): July 2003Miscanthus: October 2004Peppers (sweet): November 2006Potatoes (salad): November 2004Potentilla (shrubby): July 2002Rhododendron yakushimanum and hybrids: May 2006Runner Beans: October 2007Saxifrages (silver): May 2005Sedums (herbaceous): December 2007Spiraea japonica (with coloured leaves): November 2003

RHS Plant Assessmentonline publications, to complement RHS Plant Trials andAwards series

Pittosporum tenuifolium hybrids and cultivars: July 2006

Trials OfficeRHS GardenWisleyWokingSurrey GU23 6QBe-mail: trials@rhs.org.uk

www.rhs.org.uk/trialsReg charity no. 222879/SCO 38262

All text & images © Copyright RHS 2008

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