A low almost deciduous shrub with spreading branches; stems flattened and four-lined under the flower-clusters, the next internodes two-lined, the lower ones terete. Leaves short-stalked, mostly narrow-ovate, obtuse at the apex, 1 to 11⁄2 in. or slightly more long, 1⁄2 to 5⁄8 in. wide, greyish green beneath. Flower-buds slender, conical. Flowers 11⁄4 to 13⁄4 in. wide, cup-shaped, soft yellow, usually borne singly or in three-flowered cymes. Petals with an acute, hooked apiculus at the apex of the inner margin (as in H. kouytchense). Sepals ovate-oblong or oblong-lanceolate, with slender, acuminate tips. Stamens about half as long as the petals, in five bundles. Styles free, about as long as the ovary or slightly longer. Bot. Mag., t. 9345.
A native of W. China; introduced by Wilson in 1907-8 under W.256. Wilson sent no specimens of the wild plants from which the seeds were taken and it was not until 1924 that a garden plant raised from W.256 was identified by Rehder. He considered it to be H. kouytchense but this hypericum is in fact an allied but quite distinct species, which Dr Robson has described under the name H. wilsonii (Journ. R.H.S., Vol. 95 (1970), p. 492). The true H. kouytchense (q.v.) is a much stronger growing species, with longer, very prominent stamens.
H. wilsonii is not common in gardens but is in cultivation in the R.H.S. Garden at Wisley, where it is hardy. The plants there bear soft-yellow flowers, but they are shown as golden yellow in the plate in the Botanical Magazine.