Aeschynanthus buxifolius Hemsl.

This author first met Aeschynanthus buxifolius at Ness Botanic Gardens, Cheshire, UK, when researching for New Trees in the 2000s, and was astonished to learn that it was considered almost hardy, being grown successfully in a cold greenhouse. This was from Keith Rushforth’s 2003 collection KR 7798, from c. 2000 m in the Tram Tau to Phu Luong range in Yen Bai Province, Vietnam: it was featured in an interesting Curtis’s Botanical Magazine article by David Middleton in 2010, with fine illustrations by Masumi Yamanaka. This remains the dominant, perhaps only, collection in the UK, and has been widely distributed. More introductions have been made to North America. Steve Hootman’s SEH 27301 and 29001, also from Vietnam, have been freely available in commerce, and YuGu 306 from 1800–2000 m on Huanglianshan, Yunnan, is offered by Far Reaches Nursery, Washington. All appear to be very similar in appearance, but there are apparently differences in hardiness (S. Zoeller pers. comm. 2025). At the time of writing (January 2026) material of presumably Chinese origin is offered online by Hengduan Mountains Biotechnology Ltd, and would apparently be easily purchasable by western customers. It is not known whether anyone has been adventurous enough to purchase such material. (In France a plant is cultivated as A. austroyunnanensis by Pepiniere AOBA: online images strongly resemble A. buxifolius).

As a striking, showy member of the Gesneriaceae, with the allure of potential hardiness, the species inevitably attracts attention. It forms a tuft of more or less erect stems – their final length is uncertain, but none more than 40–50 cm or so have been observed by the author, densely clad with the small Buxus-like leaves that provide its specific epithet. The bright orange-red flowers are freely produced during the northern summer and autumn. The precise parameters of its hardiness remain under experimentation. It is established in mild coastal gardens in western Europe and the Pacific Northwest, KR 7798 surviving to at least –6°C (Middleton 2010,Gregson 2018, S. Zoeller pers. comm. 2025), though being killed at –10°C in inland Oregon (unknown provenance) (Leichty 2022), and at Far Reaches Nursery (SEH 27301) (S. Zoeller pers. comm. 2025). SEH 29001 has grown outdoors in Raleigh, North Carolina, for several years at both the JC Raulston Arboretum (in the lath house) and Juniper Level Botanical Garden (in a berm between rocks) and has survived –10°C there (though its leaves were browned by –10°C in December 2025), as well as tolerating the summer heat and humidity (Plant Delights Nursery, Inc. 2024; T.Avent, D. Ruhren pers. comms. 2025). Mark Weathington (pers. comm. 2026) says, however, that it has generally been only semi-evergreen at the JC Raulston Arboretum, and has only flowered well after a mild winter when it remained green throughout. An intriguing use in green walls in Paris has been reported by Jonathan Gregson (2018), but it is not known whether these plantings have persisted. Elsewhere it is very easily grown in a cool greenhouse or conservatory. In suitable conditions of persistent high humidity it could be grown on a mossy log, rock, or even a tree fern trunk, otherwise an open, free-draining, humus-rich medium is required. Raised beds are ideal to provide the requisite drainage, though ample moisture should be provided in the growing season. Cuttings root easily in high humidity and bottom heat. Seed will require special care, as the seedlings are minute (Huxley, Griffiths & Levy 1992).