Wildflower is published quarterly by the Wildflower Center. Its content is national in scope with articles about the conservation and use of native plants as well as news from the Wildflower Center. A subscription is provided to Wildflower Center members as a benefit of membership.
Brilliant Blooms by Lisa Halvorsen - Spring 2005
When Charles Eastman, a friend and fellow nature lover, mentioned a very fragrant white azalea that he had spotted years ago on a high bluff near Columbia, South Carolina, Mike Creel was intrigued. He also wondered why no one else had ever reported seeing it.
The flowering shrub, later named Rhododendron eastmanii in honor of Mr. Eastman, did indeed turn out to be a new native Rhododendron species. Creel speculates that it remained undiscovered for so long because it blooms in mid-May when hunting and fishing aren't allowed and snakes and insects deter all but the most ardent hikers.
Although Creel first observed it in 1989, another decade went by before Dr. Kathleen Kron, a biology professor at Wake Forest University in Winston-Salem, North Carolina, was asked to authenticate the discovery. The azalea, a white-flowered species with a yellow center that grows on steep, north-facing bluffs, was found to be a separate, but similar, species to Alabama azalea (R. alabamense).
To date the Lexington, South Carolina, plant hobbyist has documented R. eastmanii in 11 counties in the state. He believes isolated populations also may exist in Georgia, Florida, and Alabama.
Creel began propagating native azaleas from seeds and cuttings more than 20 years ago, experimenting with different propagation techniques, media, and containers. He currently grows all 16 American natives on his 7-acre homestead (USDA plant hardiness zone 8a), which is located on the fall line where the Piedmont and coastal plain meet. Fifteen are native to the east and one - the western azalea (R. occidentale) - has a limited native range on the West Coast.
Rhododendron comes from the Greek words rhodo (rose) and dendron (tree). The genus, which includes around 850 native evergreen and deciduous woody shrubs and trees, belongs to the Ericaceae (heather) family. Two of the eight sub-genera are azaleas - Pentanthera (deciduous azaleas, including North American natives) and Tsutsusi (evergreen azaleas, mostly Japanese natives) which were once considered a separate genus.
Although many people mistakenly believe that azaleas and rhododendrons are the same, the two, while closely related, are different. Generally, rhododendrons have 10 or more stamens, evergreen leaves with or without scaly undersides, and bell-shaped flowers. Most azaleas have five stamens, hairy deciduous leaves, and funnel-shaped flowers.
The Rhododendron genus includes many showstoppers with spectacular blooms in colors ranging from orange, red, pink, rose, magenta, and lavender to yellow and white. Some are incredibly fragrant, while others have no discernible scent. The flowers grow in rounded clusters or trusses with as many as 12 to 15 individual blossoms on each. Leaves can be as small as 1/4-inch or as big as 3-feet long and be round, lance-shaped, or elliptical, depending on the variety.
While the largest amount of Rhododendron species are natives of Asia, including R. fortunei, a Chinese species that's the parent plant for many popular hybrids, others are found in northern Europe, North America, and Australia in a wide diversity of habitats from coniferous and alpine woodlands to temperate rainforests.
Twenty-six species are native to the United States, according to Steve Hootman, curator and co-executive director of the Rhododendron Species Botanical Garden in Federal Way, Washington, one of the world's largest rhododendron collections with more than 10,000 plants representing 480 species.
"In our climate, rhododendrons are the backbone of most gardens," Hootman points out. "You can create an entire garden of these species because of the different textures, forms, colors, and bloom times. There are deciduous and evergreen species ranging in height from ground covers only a few inches high to 100 feet tall."