Buddleja davidii var. alba is endemic to central and western China.Bean, W. J. (1917). Trees and shrubs hardy in Great Britain, 7th edition. Murray, London. The plant has also been treated as a form, and a cultivar ('Alba').Hatch, L. (2007) Cultivars of Woody Plants Volume I (A-G) 2007 Edition. TCR Press Horticultural PDF. books. However, Anthonius Leeuwenberg sank var. alba and the other five varieties of davidii as synonyms,Leeuwenberg, A.J.M. (1979). The Loganiaceae of Africa XVIII Buddleja L. II. Revision of the African and Asiatic species. H. Veenman & Zonen B. V., Wageningen, Nederland considering them to be within the natural variation of a species, a treatment also adopted in the Flora of China published in 1996,Li, P-T. & Leeuwenberg, A. J. M. (1996). Loganiaceae, in Wu, Z. & Raven, P. (eds) Flora of China, Vol. 15, p. 335. Science Press, Beijing, and Missouri Botanical Garden Press, St. Louis, USA. online at www.efloras.org and is also upheld by both the Plants of the World Online database and the International Dendrology Society's Trees and Shrubs Online website.
Description Buddleja davidii var. alba is distinguished by its inflorescences of white flowers with yellow eyes, considered inferior to many of the white cultivars now in commerce, and narrower leaves.
Cultivation Now rare in cultivation, var. alba is still grown in the UK at the Sir Harold Hillier Gardens near Romsey, and at the Royal Horticultural Society's garden at Wisley in Surrey.
Suppliers There is one nursery in the UK marketing the shrub, listed in the RHS Plantfinder.
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