Rhododendron (Yakushimanum) 'GOLDPRINZ' ('Goldschatz') rhododendron

Rhododendron

Rhododendron is a large genus within the Ericaceae family, currently comprising around 1,000 recognized species, with the greatest species diversity found in the Himalayas, southwestern China, and the Japanese archipelago. The natural range of the genus extends from Arctic regions of the Northern Hemisphere through the montane forests of Europe and Asia to the tropical cloud forests of Southeast Asia and New Guinea; fossil and molecular evidence points to an ancient origin with major diversification during the Tertiary and Neogene periods. Rhododendrons reached Europe on a larger scale in the 18th and 19th centuries through collecting expeditions and botanical gardens; among the early key figures were Francis Buchanan‑Hamilton (1762–1829) and Nathaniel Wallich (1786–1854), followed later by Robert Fortune (1812–1880). A major breakthrough came with the work of William Jackson Hooker (1785–1865) at Kew and subsequently his son Joseph Dalton Hooker (1817–1911), who during expeditions to Sikkim and the Himalayas described and introduced dozens of new species, profoundly influencing modern breeding. The tradition of plant collecting and breeding was later continued by Ernest Wilson (1876–1930) and others.

Rhododendron yakushimanum is a species native to the small Japanese island of Yakushima, discovered in montane forests and scrub at elevations of approximately 1,200–1,800 m, growing on well‑drained granitic soils and often in full sun, forming low, wind‑resistant shrubs with a dense, compact habit. Takenoshin Nakai (1882–1952) described it as a distinct species, although it was later treated as R. metternichii var. yakushimanum. A defining feature of the species is its indumentum – the felted covering of young leaves – which reduces water loss and protects foliage from temperature extremes and wind. After the first plants were introduced to Europe in the first half of the 20th century by the Japanese grower Koichiro Wada, who sent material to Great Britain between 1930 and 1934, R. yakushimanum rapidly became a cornerstone parent in the breeding of compact, hardy, and highly ornamental hybrids, combining the resilience of yakushimanum with the often more vivid flower colouration or distinctive leaf textures of less hardy parents.