National Council for The Conservation of Plants and Gardens
National Collection of the Genus Codonopsis and Allied Genera
A large, vigorous twining climber not often seen, seed lists usually proving to be Cc rotundifolia var. angustifolia or pilosula. This is surprising since C.tangshen is the only member of the genus, at least as far as we are aware, with an inferior calyx i.e. the calyx lobes completely enclose the calyx when the flower opens. The large flowers are greenish throughout with internal markings and the seeds are large and brown . C.tangshen will hybridise with others and we have grown a rather attractive hybrid in the past (see photo below).
Another diagnostic is the very striking purple seed capsule, not something we've noticed on any otherwith the exception of C.javanica which we have seen growing at Kew.
China. Much used in Chinese medicine