Plant of the Week: Coral Bells Azalea
Plant of the Week
Coral Bells Azalea
Latin: Rhododendron indicum 'Coral Bells'
Homeowners across the state are carrying home azalea bushes by the thousands as they
come into bloom at their favorite retail outlet.
Of the large azalea tribe, the Kurume azaleas are the most popular hybrid group in Arkansas, with Coral Bells azalea being the most common selection of this group. Given that all of these plants are sold every spring, why don’t our mature landscapes show more evidence of azaleas in the spring?
"Coral Bells" is a compact shrub capable of growing six feet tall and wide. It is evergreen and hardy as far north as zone 6b, thus including all of Arkansas. It blooms in midseason, usually about the end of March in south Arkansas and about mid March in northern areas. The blooms are pink and produced in abundance even on small plants. The flower is a double with one whorl of petals nested neatly inside the other -- a character known as "hose-in-hose" to azalea specialists.
The Kurume azaleas were first introduced into this country at the Panama-Pacific Exposition held in San Francisco in 1915 which celebrated the August 1914 opening of the Panama Canal. The Domoto Brothers, nurserymen of Hayward, Calif., purchased some of the plants at the exhibit and, recognizing their commercial potential, visited the village of Kurume in southern Japan in1917. There they found that over 250 kinds of Kurume azaleas had been developed over the last century by Japanese hobbyists who had collected hardy plants from the sacred 5,500-foot Mount Kirishima on Kyushu Island, the most southerly of the four main Japanese islands.
The Domoto brothers formed a company to import plants and to distribute them in the U.S. market. Many of their 32 different Kurumes were sold through Long Island and New Jersey nurseries, thus getting them firmly established in the U.S. nursery market. Among the
English-named cultivars they popularized are the still common "Appleblossom," "Bridesmaid," "Christmas Cheer," Coral Bells, "Flame," "Pink Pearl," "Salmon Beauty" and "Snow."
The Arnold Arboretum’s plant explorer, E. H. Wilson, had better press connections and is often given credit for introducing Kurume azaleas, but his 50 introductions did not arrive in Boston until 1919. Many of Wilson’s Kurumes overlapped the Domoto introductions. To further add to the confusion, both introducers independently developed English names for their set of introductions. Coral Bells -- the Domoto name for the most beautiful hose-in-hose pink azalea of the Kurume tribe -- was called by Wilson "Daybreak" and "Kirin" by its Japanese breeder.
Of the thousands of Coral Bell azaleas planted each year, surprisingly few survive to have much impact on the mature landscape. Azaleas are not plant-them-and-forget-them kinds of plants. Gardeners not willing to do some up front work to establish the correct growing conditions and provide ongoing maintenance should look elsewhere for their floral adornment. Azaleas require an acid soil pH of around 5.5 and really good drainage. The soil requirements are most conveniently met by planting azaleas in raised -- or at least mounded -- beds consisting largely of sphagnum peat moss or aged pine bark. Once planted in these highly organic soils, the shallow roots will spread quickly but the planting bed also dries quickly. Plants must be watered often during summer dry periods and fertilized as per the recommendations given on any of the common azalea fertilizer products.
Azaleas lacebug, a serious insect pest that can turn azalea leaves white by late summer, should be scouted for in May. Insert a piece of plain white paper into the canopy of the plant and then shake vigorously. If any small, squarish tan colored insects are found, spray with an insecticide such as Orthene to prevent the population from getting established during the summer.