A semi-evergreen, laxly branched shrub 2 to 4 ft high; stems beneath the inflorescence flattened. Leaves ovate to narrow-ovate, 11⁄2 to 21⁄4 in. long, 5⁄8 to 7⁄8 in. wide, acute at the apex, medium green above, pale beneath, shortly stalked. Flower-buds narrowly ovoid to almost conical, acute, slightly more than twice as long as wide. Flowers light golden yellow, about 21⁄2 in. wide. Sepals lanceolate to ovate-lanceolate, rather spreading, with slender acuminate tips. Petals spreading or reflexed, with a hooked acute apiculus at the apex of the inner margin (i.e. the longer, thicker margin). Stamens a very prominent feature of the flower, about three-quarters as long as the petals, in five bundles. Styles free, as long as the ovary or slightly longer.
Native of Kweichow, China, whence it was introduced to Maurice de Vilmorin’s collection at Les Barres around the turn of the century by one of the French missionaries. It appeared in Britain under the name H. patulum grandiflorum, but its provenance was uncertain and its long, prominent stamens gave rise to the theory that it might be a hybrid of garden origin, with H. stellatum (H. “dyeri” of gardens), or H. calycinum, as one parent. But Dr Robson has found that this hypericum agrees well with the type-specimen of H. kouytchense, now preserved at Edinburgh, and that the hypericum introduced by Wilson under W.256, which Rehder had identified as H. kouytchense, represented a distinct, hitherto undescribed species (see H. wilsonii). It should be added, however, that some plants distributed commercially as H. kouytchense before 1970 are not H. wilsonii but H. acmosepalum.
H. kouytchense is a very hardy and decorative species, flowering from midsummer until September. Its characters are well shown in the drawing by Graham Thomas in Gard. Chron. (April 16, 1960), p. 255 (as H. penduliflorum). The ripening capsules turn bright red soon after the petals drop.