Seeking Cold-Hardy Camellias - Arnold Arboretum - Arnoldia

28 Arnoldia 67/1Anthony S. AielloSingle, red flowers were standard for the Korean seedlings, though some plants had more vibrant color or greaternumbers of flowers.Currently we are planning to name and introduceseveral individual plants from our Camelliajaponica trials (see sidebar). Two of theseplants are those that show the highest ratingsfor combination of plant habit, foliar quality,and flower density. One plant shows a strikingupright habit and a fourth is consistentlyprecocious, regularly blooming in late autumncompared to the normal early spring bloomingtime of the species.Presently there are three commerciallyavailable introductions from the 1984 KoreanCamellia japonica collections. These are:‘Korean Fire’ (KNW 352) a 2003 PennsylvaniaHorticultural Society Gold Medal winner thatwas introduced by Barry Yinger through HinesNursery (Bensen 2000); and ‘Longwood Valentine’and ‘Longwood Centennial’ (KNW 350)introduced by Longwood Gardens (TomaszAniśko, personal communication).Going forward, our goal is to distribute ourselections and compare them to other knowncold-hardy forms of Camellia japonica. Weare also working with plant breeders to sharematerial in the hope that the hardiness inherentin our plants can be utilized to develop coldhardyvarieties with greater variation in flowercolor and form. Much of the work in developingcold hardy camellias has been conductedby Dr. Ackerman and Dr. Parks (Aniśko 2000).Additionally, Longwood Gardens continues along research program in breeding and selectingcamellias (Aniśko 2000).The evaluation of woody landscape plantsis a long-term commitment, one that oftenspans the tenures of staff at institutions that

30 Arnoldia 67/1Paul W. MeyerChinese origin (Aiello 2005). Likewise, aftermore than 20 years of evaluation, the KoreanCamellia japonica plants represent some of themost cold-hardy collections ever made of commoncamellia. These collections may extendthe hardiness of Camellia japonica into morenorthern areas and bring the spring pleasure ofcamellias to eager gardening audiences.AcknowledgementsThe author would like to thank Elinor I. Goff, MichelleConners, Shelley Dillard, and Sara Ranck for theircontributions to this project and to this article.Literature CitedAckerman, W.L. 2000. Northern Exposure. AmericanNurseryman 192 (11): 38–43.Ackerman, W.L. 2007. Beyond the Camellia Belt. BallPublishing, Batavia, Illinois.Ackerman, W.L. and D.R. Egolf. 1992. ‘Winter’s Charm’,‘Winter’s Hope’, and ‘Winter’s Star’ Camellias.HortScience 27: 855–856.Aiello, A.S. 2005. Evaluating Cornus kousa cold hardiness.American Nurseryman 201 (5): 32–39.Aiello, A.S., S. Dillard, E.I. Goff, and M. Conners. 2008.Evaluation of cold hardiness and ornamentalcharacteristics of Korean provenances ofCamellia japonica. Royal Horticultural Society:The Rhododendron, Camellia & MagnoliaGroup Yearbook: 26–31.Aniśko, T. 2000. Collection Service. AmericanNurseryman 192 (11): 44–50.Bensen, S.D., ed. 2000. New Plants for 2001: Shrubs.American Nurseryman 192 (12): 34.Flint, H.L. 1997. Landscape Plants for Eastern NorthAmerica. 2nd Edition. John Wiley and Sons,New York.A Camellia japonica grown as an espalier in a protected spot atthe Morris Arboretum.collect, propagate, and evaluate these plants.At the Morris Arboretum we have found thatplants collected in the 1980s in South Koreahave exceptional cold hardiness and adaptability.For example, stems from Cornus kousa thatwere also collected on the 1984 KNW expeditionshowed significantly more freezing tolerancein tests than plants of either Japanese orMeyer, P.W. 1985. Botanical riches from afar. MorrisArboretum Newsletter 14 (1): 4–5.Yinger, B. 1989a. Plant Trek: In pursuit of a hardy camellia.Flower and Garden 33 (2): 104–106.Yinger, B. 1989b. Plant Trek: On site with hardy camellias,Sochong Island, Korea. Flower and Garden 33(3): 62–66.Anthony S. Aiello is the Gayle E. Maloney Directorof Horticulture and Curator at the Morris Arboretumof the University of Pennsylvania in Philadelphia,Pennsylvania.