Buddleja coriacea

Buddleja coriacea typically makes a densely crowned, sprawling trioecious shrub or tree, branching almost at ground level. Usually growing to less than 4 m in height in the wild, it can occasionally reach 12 m, with stems up to 40 cm in diameter; the bark is fissured.[2][1] The species is chiefly distinguished by its small, thick, leathery leaves, 1–4  cm long by 0.5–1.5 cm wide, with 3–4 mm petioles. The upper surfaces of the leaves are dark-green and glabrous, contrasting with the undersides which are covered in a cinnamon-brown indumentum. The scented inflorescences comprise 3–8 pairs of head-like cymes, 0.9–1.2 cm in diameter, of 8–12 flowers, the corollas 4.5–6 mm in length, deep yellow to orange-yellow, becoming orange-red with age. Flowering occurs throughout the year, but most commonly between December and June. Ploidy: 2n = 76 (tetraploid).[1]

Buddleja coriacea is cultivated in the high Andes as a field windbreak, as a source of humus for soil improvement, and as high quality, rotproof timber for use in building construction and manufacture of agricultural tools.[3] The shrub was introduced to horticulture in the UK circa 1994, and specimens are held as part of the NCCPG national collection at the Longstock Park Nursery, near Stockbridge.[4] Although not entirely hardy in the UK, the shrub can survive most winters with a modicum of protection; overwinter waterlogging regarded as a greater danger to the plant. The shrub has never been known to flower in the UK owing to either the insufficient intensity or duration of sunlight. Hardiness: USDA zone 9.[5]

The species is believed to commonly hybridize with B. montana and B. incana in the wild.[1]

• Cruz, N., Morales, M, & Rojas, E. (2000). Buddleja coriacea. Fichas Tecnicas de Especes Forestales (in Spanish). BASFOR, Bolivia.