Scientific Name: Rhododendron occidentale
Common Name: Western azalea
Plant Type: Shrub
Environment: Regular water during dry weather; well-drained soil; full sun to partial shade; important to keep root ball cool and protected.
Bloom: Large four inch fragrant flowers from white to deep pink with yellow-orange blotch appear in April and May.
Other: Like all plants in the Ericaceae (heather) family, R. occidentalehas poricidal anthers, appearing as two black dots at the end of each anther. The function of these pores is to release pollen. Azalea is a section in the genus Rhododendron and is often used as the common name for the smaller flowered, shrubbier Rhododendron in the trade.
Rhododendron occidentale is one of the West Coast's showiest shrubs. Native to California and Southwestern Oregon, it can be found in a variety of habitats from foggy coastal scrub to coast redwood forests as well as in serpentine soils. First reported in a publication by Sir William Hooker in 1857, the discovery of the western azalea dates back to the 1820s.
Western azalea's flowers are funnel-shaped and typically four inches long, two to three inches wide and wonderfully fragrant. The corolla has five lobes (petals) generally white to deep rosy pink with an yellow-orange blotched marking on the inside of the upper lobe. New foliage emerges a bright glossy green and, along with buds, pedicels and seed capsules are covered with oil glands that fall off during the season.
Western azalea is deciduous, and in autumn the leaves turn golden-yellow before falling. They can reach five to 15 feet but are slow growing and often challenging to grow in cultivation. In growing the western azalea over the years, we have learned that providing routine moisture and a cool, protected root zone is critical to its success.
IN BLOOM CONTRIBUTORS:
Photos by Docent Joanne Taylor; text and profile by Associate Curator David Kruse-Pickler; additional photos provided by David Kruse-Pickler.