A vigorous evergreen shrub to 7 ft high and eventually more across, with stout yellow-grey stems armed with flattened spines. Leaves elliptic to elliptic-ovate, about 2 in. long, leathery, glossy green above and glaucous grey beneath, with a few rather distant teeth. Flowers borne on stalks 1⁄2 in. long, in clusters of three to six. Berries glaucous blue, about 1⁄2 in. long.
Native of Upper Burma, introduced by Farrer from Hpimaw in 1919 and originally considered to be a form of B. hookeri, to which it is indeed closely related. It was recognised as a distinct species by Schneider and named by him after E. H. M. Cox, Farrer's companion in Burma and the founder and editor of the incomparable New Flora and Sylva, which ceased publication in 1940 but is still much read and consulted by plant-lovers. B. coxii is a fine evergreen, bushy and of good habit. Mr Cox tells us that the original plants at Glendoick, planted forty years ago, are now about 6 ft high and 14 ft across.