Buddleja officinalis largely resembles the commoner B. davidii in shape and size, growing to less than 2.5 m in height. The inflorescences are honey-scented mauvepanicles, shorter (under 8 cm) than those of davidii, and more conical. The leaves are lanceolate, under 15 cm long, softly pubescent, the upper surface rich green in colour, the underside grey.[1] 2n = 38.[5]
Cultivation
Buddleja officinalis is not fully frost hardy, unable to survive temperatures lower than −10° C, and is best grown against a south-facing wall.[1] The shrub should be cut back hard each year immediately after flowering in spring. Propagation by softwood cuttings is easily accomplished, using vermiculite as a rooting medium.
^ abcPhillips, R. & Rix, M. (1989). Shrubs. Pan Books, London. ISBN0-330-30258-2
^Bryce, W. J. (2007). Pavel Yakovlevich Pyatsetski (1843 – 1919): his botanical collections in China (1875) and paintings of Chinese gardens. Archives of Natural History. Vol. 39, 171–174. ISSN0260-9541, E-ISSN 1755-6260. Edinburgh University Press.
^Hillier & Sons. (1977). Hilliers' Manual of Trees and Shrubs, 4th Edition. David & Charles, Newton Abbot, England. ISBN0-7153-7460-5
^Chen, G, Sun, W-B, & Sun, H. (2007). Ploidy variation in Buddleja L. (Buddlejaceae) in the Sino - Himalayan region and its biogeographical implications. Botanical Journal of the Linnean Society. 2007, 154, 305 – 312. The Linnean Society of London.
^Brookes, A. H. (2007). Winter flowering buddlejas. Plant Heritage: Hampshire and Isle of Wight Group, Spring 2007.. Plant Heritage, UK.
Leeuwenberg, A. J. M. (1979) The Loganiaceae of Africa XVIII Buddleja L. II, Revision of the African & Asiatic species. H. Veenman & Zonen, Wageningen, Nederland.
Li, P. T. & Leeuwenberg, A. J. M. (1996). Loganiaceae, in Wu, Z. & Raven, P. (eds) Flora of China, Vol. 15. Science Press, Beijing, and Missouri Botanical Garden Press, St. Louis, USA. ISBN978-0915279371online at www.efloras.org