A deciduous azalea, closely allied to R. japonicum. The most obvious difference is that the leaves of R. sinense are coated beneath throughout the season with a dense felt of soft down and that the buds, too, are conspicuously downy. The calyx-lobes are shorter and not so bristly, and the flowers are always in some shade of yellow.
R. molle, once better known as Azalea sinensis, is common in Chekiang, China, and also occurs in other provinces of eastern China. According to Wilson it grows among coarse grasses and shrubs and in thin pinewoods, and makes a small, sturdy shrub 2 to 5 ft high. Fortune is very eloquent of its beauty as seen wild in China, especially on the hills about Ningpo, where, he wrote, ‘the yellow Azalea sinensis seemed to paint the hillsides, so large were the flowers, so vivid the colours’. Fortune sent seeds in 1845, hut there had been an earlier introduction to Loddiges’ nursery, in 1823. In this century, seeds have been collected by Wilson near Ichang, in W. Hupeh, where the species is near its western limit, and also by Forrest, who found it growing in a lamasery garden (F.25477). Another reintroduction was by Rock under his no. 59226, from the foot of the Litiping range in Yunnan, but it is not clear whether the plants were wild or cultivated. This sending is of interest, since plants raised from it were used by Lionel de Rothschild in the breeding of the Exbury strain of the Knap Hill azaleas.
R. molle is hardy, but lacks stamina and has always been rare in gardens. But, by crossing with the more vigorous R. japonicum and other azaleas it has given rise to some of the finest of the yellow-flowered hybrids. It is also a parent of the azaleodendrons ‘Broughtonianum Aureum’ and ‘Smithii Aureum’. See further in the section on hybrids.