Rhododendron is the largest woody plant genus in the world with about 1000 species. Most of them have large, evergreen leaves and numerous, large flowers.
Rhododendron is the largest woody plant genus in the world with about 1000 species. Most of them have large, evergreen leaves and numerous, large flowers. They are found throughout the Northern Hemisphere, with two species found in Norway: Lapland rosebay (R. lapponicum) and marsh Labrador tea (L. tomentosum). However, the two large diversity centres are the Yunnan and Sichuan provinces in western China and Indonesia, with adjacent areas. The latter area is home to about 300 species from tropical mountain forests.
Until the 1980s it was believed that cultivation of rhodo-dendrons was impossible in Tromsø. However, our collection now includes more than 70 species, in addition to hybrids. Among these, about 30 species are from the hardy Taliensia group, where the leaves have brown-tomentose lower sides. Those with intensely red flowers are in the Neriiflora group. Three Europeans are in the Alpenrose group, whereas many small-flowered species belong to the group Lapponica. Leaf-shedding species are called Azaleas. The yellow Rhododendron wardii can grow more than 2 m tall in Tromsø.
Rhododendrons belong to the Heather family, which is so important in our native flora. Some other genera are represented here, such as mountainheaths (Phyllodoce) and bell-heathers (Cassiope). Primulas, poppyworts and lilies are grown as ‘visual supplements’ in the collection.