Rhododendron arboreum
Common name: Himalayan tree rhododendron
The famous Rhododendron arboreum is one of the world’s tallest rhododendrons. Plants can grow to an incredible 40 m (130 ft) high. It is a variable species with a range that includes the mountains of western China and adjacent Vietnam, Myanmar and India, northern Thailand, Nepal, Bhutan and Sri Lanka.
Tree rhododendron’s thick, leathery leaves are mostly oblong to about 20 cm (8 in) long. The flowers are borne in rounded trusses of about twenty flowers. The species can vary in leaf size, white to dark brown indumentum (felty-like hairs on back of leaves), and flower colour. The flower colour can be white, and various shades of lavender, pink and red.
R. arboreum subsp. cinnamomeum var. album is native to Nepal. This white-flowering tree has leaves a little shorter than those of a tree rhododendron, with a two-layered indumentum. The lower layer is whitish to fawn-coloured, while the upper layer is rust-coloured, loose and woolly. This is not the rhododendron species in Nepal that the much sought after Mad Honey comes from, but the bees still love it. In 1820 Dr. Nathaniel Wallich collected its seeds in Nepal and sent them to a variety of places in England.
The pictures were taken in the Sino-Himalayan Garden in early May on the trail going through bed 122. You can also find this tree rhododendron growing in the Fern Dell and at the beginning of the Rhododendron Walk.
Text and photos by Hughie Jones