Buddleja brachystachya is a small shrub endemic to the Yunnan, Sichuan and Gansu provinces of China, where it grows on open, rocky, often dry, places at altitudes of 2,000–2,400 m. It was first described and named by Diels in 1912.Diels, F. L. E. (1912). Notes Roy. Bot. Gard. Edinb. 5: 249. 1912.
Description Buddleja brachystachya grows to 0.3–0.9 m in height, with subquadrangular to subterete, densely stellate-tomentose branchlets. The small, opposite leaves have elliptic blades, 1–3.5 cm long by 0.5–1.7 cm wide, acute or obtuse at the apex, cuneate or decurrent at the base, the margins entire. The lavender inflorescences are small, thyrsoid, and often few-flowered, 1.5–3 cm long by 1.5–2.5 cm wide, the corollas 11–18 mm long.Leeuwenberg, A. J. M. (1979) The Loganiaceae of Africa XVIII Buddleja L. II, Revision of the African & Asiatic species. H. Veenman & Zonen, Wageningen, Nederland. . Ploidy 2n = 38 (diploid).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.
Cultivation The species is uncommon in cultivation. Hardiness: USDA zone 10.Stuart, D. (2006). Buddlejas. Plant Collector Guide. Timber Press, Oregon, USA.
References
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. online at www.efloras.org