Dwarf shrub, perhaps epiphytic, to at least 1 m in cultivation; young shoots bristly. Leaves to 8.8 x 4.5 cm, oblong-elliptic, apex obtuse, lower surface papillose, with close golden-yellow scales slightly sunk in pits. Pedicels very short, densely scaly. Flowers 3-4 per inflorescence; calyx with obscure lobes 2-3 mm long; corolla yellow, campanulate, c.30 mm (to 40 mm in cultivation); tube c.15 mm, outer surface pubescent at base, pilose within; stamens 10, regular; ovary scaly, tapering into the sharply deflexed style. Flowering March-April.
This is a tender plant, only suitable for gardens with a relatively frost-free climate. Royal Horticultural Society (1997)
RHS Hardiness Rating H3
Awards AM 1934 (Lord Aberconway, Bodnant); flowers clear yellow. This may be a hybrid.
Conservation status Data deficient (DD)
Taxonomic note It is intermediate between and might be a hybrid of R. yungchangense and R. sulfureum. Royal Horticultural Society (1997)
An evergreen small shrub; young shoots sparingly bristly. Leaves oval, rounded at the base, also somewhat rounded at the apex but furnished with a conspicuous mucro there; mostly 2 to 3 in. long, 1 to 11⁄2 in. wide, bright green and glabrous above, glaucous green and scaly beneath, more or less ciliate; stalk 1⁄3 to 1⁄2 in. long, bristly. Flowers in terminal clusters of about five. Calyx rimlike. Corolla bell-shaped, 11⁄2 in. long and wide, with five lobes each 1 in. wide, notched about the middle, of a beautiful unspotted canary-yellow; stamens downy on the lower half. Ovary and flower-stalk very scaly; style bent. Bot. Mag., t. 9442. (s. and ss. Boothii)
This species first came to notice in 1931, when Lord Stair sent it to Edinburgh for naming. It had been raised from seeds received under the number Forrest 25446 and probably collected in N.W. Yunnan, but the corresponding herbarium specimen is R. ciliicalyx and the field note refers to this. It proved to be a hitherto unknown species and was given the name R. chrysodoron but this was first published in 1934 by Hutchinson, who drew up his description from a flowering spray shown by Lord Aberconway at the R.H.S. Show on February 20. It received an Award of Merit on that occasion as a hardy shrub, but it is generally reckoned to be tender and is, besides, too early-flowering to be of much use as an outdoor plant, March or early April being its usual season. It is, however, a beautiful species, not too large for the cool greenhouse.
R. chrysodoron is also in cultivation from seeds collected by Kingdon Ward in the Adung valley, upper Burma, where it grows perched high on trees or on rocks in the river-bed (Field Notes for 1931, under KW 9221; Plant Hunter’s Paradise, p. 132).
Forrest 25446, mentioned in the second paragraph on page 630, is not R. ciliicalyx but a new species – R. yungchangense Cullen. However, the cultivated plants supposed to be from this seed collection are R. chrysodoron, as stated.