We are all probably use to seeing the flowers of rhododendrons as large, brightly coloured trusses. However, Rhododendron spinuliferum provides us with a unique insight to the variation that there is in the large genus of Rhododendron. Rhododendrons are as diverse in their appearance as they are in their distribution throughout the world. Generally rhododendrons naturally occur across the Northern Hemisphere even as far as the Arctic Circle. Then from the northeastern United States of America to the extremes of Western Europe (Siberia) and down to northern Japan. The greatest concentration of rhododendrons is in the area where the Himalayas, the Xizang (Tibetan) Plateau and the mountain ridges of Burma and southwest China meet.
We should not forget the tropical or so called Malesian species that occur from and including the Malay Peninsular across to the northern tip of Australia. The greatest density of the Malesian species is in Papua New Guinea. We mainly know the tropical species as vireya rhododendrons.
The red tubular flowers of Rhododendron spinuliferum with its centrally protruding stamens and style provide an unusual and bright display. One of the early flowering rhododendrons, Rhododendron spinuliferum is naturally restricted to the Yunnan Province in China and is generally found in woods and shady thickets at altitudes between 800 - 2440 m. This natural occurrence provides us with some useful growing information for a garden situation. Rhododendron spinuliferum prefers a cool sheltered shady position in soil that has a fair content of organic matter. The soil for Rhododendron spinuliferum should be acidic with a pH between 4 to 6. This is in the mid acidic range of soil. Rhododendron spinuliferum can be found in the Rhododendron Species area above the basalt rock out crop behind the Barbecue Area.