Let’s make the perfect Rhododendron environment. Add lots of moisture to a rich, acidic soil; give me dappled sunlight – not strong but bright; leaf litter would be nice to conserve moisture and add microbes; and, add moderate temperatures – never too hot and seldom too cold. What grows in such a pristine mix of earthly love and forest charm? A Rhododendron, of course, and along the highlands of the Pacific coast – the Coast Rhododendron, Rhododendron macrophyllum, grows prolifically.
The Coast Rhododendron is native to the temperate rain forests of California, Oregon, and Washington. It has large, leathery evergreen leaves and blossom explosions can be ten inches across. The plant itself is a large bush occasionally exceeding twenty feet tall and with plenty of light will form a pincushion covered with purple panicles in spring and early summer. If it doesn’t receive enough light, the branches will struggle upward forming a more open tree-like form with fewer blooms.
There are thousands of varieties of Rhododendrons and they have a worldwide distribution. The most diversity in number of species is in China and Malaysia. The “Rhodo” is the national flower of several Asian countries and is extensively cultivated in Japan and India as well as China.
On Rhododendron registries maintained by several countries, over 28,000 varieties are listed and many are available in seed or potted form from nurseries and organizations such as the American Rhododendron Society of which I am a member.
On average, rhododendrons are larger shrubs than azalea plants, and they have larger leaves. Also, azalea flowers usually have five stamens, while the rhododendron flowers have ten. The stamens of a flower are those thin stems sticking out (they are male flower parts and produce pollen). Finally, unlike rhododendrons, many azalea plants are deciduous. Azaleas usually have only a few flowers in a clump or truss while Rhododendrons have a large truss with many blossoms. Rhododendrons have scales on the underside of their larger leaves while azaleas leaves are hairy. With so many varieties, there will be some overlap in characteristics and it can be difficult on some varieties to properly classify. To further confuse you, Heathers, Andromeda, and Mountain Laurel are cousins but do not interbreed. I grow Andromeda, or Pieris, and they are a beautiful evergreen shrub which complement an Azalea or Rhododendron garden.
We could talk Rhododendrons for hours but we must move on to the Appalachian state of West Virginia and a different Rhododendron.
74 Journeys 