hybrid groups || overview | aichele | amoena | arendsii | aromi | aronense | back acres | bowie mill (Clagett) | dodd confederate | encore | gable | glenn dale | greenwood | haag | harris | holly springs | huang | kehr | kurume | kiusianum | linwood | north tisbury | other | robin hill | satsuki ||
Azaleas have been hybridized for hundreds of years. Over 10,000 different cultivars, or cultivated varieties, have been registered or named, although far fewer are being propagated and sold. They provide a wide variety of plant habits, sizes, colors and bloom times to meet almost every landscaping need or personal preference.
While many azalea enthusiasts have created hybrids for their own enjoyment, a relatively small number of hybridizers have created most of the named hybrids. Since it takes many years and a lot of work to make the crosses, grow the seedlings, and evaluate the results, fewer yet have created large numbers of named hybrids.
The hybrids created by one hybridizer are termed a hybrid group. This page introduces a few hybrid groups, with links to more details on the cultivars. Cultivar names which appear as links have an image – click the link to see the image, and click your browser back button to return to the description.
C.F. Aichele, F.J. Aichele Sr. and his son James began breeding azaleas in 1948 at Carolina Flora Nursery in Mt. Holly, South Carolina Over 10,000 seedlings were grown: six were selected as the best for hardy, greenhouse-forcing azaleas. All are compact form, and blooms are hose-in-hose. See Galle85 p. 183 or IRRC 04.
The Amoena hybrids are derived from the “Amoenum” azalea introduced from Shanghai ca. 1850—which is a Japanese rather than a Chinese azalea. This azalea has small, purplish red hose-in-hose flowers on a compact plant known for its hardiness.
It should be noted that the “Amoenum” was itself probably a hybrid related to R. kiusianum according to Dr. August Kehr, JARS 43n2 – An In-Depth Look At Evergreen Azaleas
Hybridization of the Amoenum began by 1860 and many of these old hybrids exist, but without much detail as to the hybridizer. All are hose-in-hose, and are hardy in zones 6b-9
For more information and a list of hybrids see Galle 85 p. 131-4.
The Aromi azalea hybrids were created in Mobile, Alabama by Dr. Gene Aromi, a retired education professor at the University of Southern Alabama, and his wife Jane, a retired elementary school teacher. As documented in the Summer 2003 issue (25:2) of The Azalean, they began their hybridizing program in 1969 to develop evergreen azaleas with “large flower size, early bloom time, improved bud hardiness, compact habit, and array of flower forms, and rich colors”. They have named 31 evergreen azalea hybrids, described on our Aromi evergreen page.
In 1971 they began hybridizing Exbury azaleas with southern native species to create heat tolerant, large flowered, fragrant deciduous azaleas. Over 100 of these deciduous hybrids are named, and 8 of them are registered (shown in the list with an ® after the name). The deciduous azalea hybrids are described on our Aromi deciduous page.
They numbered the first selection from the first cross A-1, the first selection from the second cross B-1, and so on. Thus, for example, AAY-3 is the third selection from the 26+(26*26)+25 = 727th cross.
Other accounts of the Aromi’s hybridizing programs are in the September 1999 issue (21:3) of The Azalean, and the Winter 2002 issue (56:1) of the Journal ARS.
Developed by George Arends of Wuppertal-Ronsdorf, Germany ca.1950 from a seedling that is very similar to R. kiusianum, but is more compact and has brighter flower color. He named this seedling ‘Multiflora’ and supposedly crossed it with R. mucronatum, or perhaps some of the Arendsii Hybrids. The named cultivars of this group are dwarf, profusely-flowering plants with a larger color range than what was previously available in the Kiusianum Hybrids. They were introduced by the G. D. Bohlje Nursery of Westerstede, Germany, during the early 1960s. See Matt Nosal’s paper in QBARS – v33n3 Dwarf Azaleas from Germany
Plants are very hardy, tested to 0°F, have small hairy leaves and low mounding habit. 18”-24” high. See Galle 85 p. 258 for a list of hybrids
dodd confederate series
The Confederate Series of Native Azaleas were selected from a cross of Rhododendron austrinum and Rhododendron x ‘Hotspur Yellow’. This cross was made by Bob Schwindt, the seed were planted by Dad and Tom III made the evaluations and named them per Mr. Schwindt’s request. We had always loved the Exbury Azaleas but they can’t take the heat of the deep south. The R. austrinum blood gives them the heat tolerance and vigor that we need here. Below is a list with the colors, etc. Most of them are difficult to propagate and grow, but do well once they are planted in semi-shade with good drainage. Members of this series are listed on the Dodd’s Confederate Series page.
Encore azaleas were developed by Robert E. “Buddy” Lee of Independence, Louisiana over the past fifteen or more years. They are a true multi-season blooming hybrid group which has become widely available due to their bloom, size, and hardiness. Please go to our Encore page for a list of available hybrids and their colors.
B. Y. Morrison, Director of the U.S. National Arboretum, began an ambitious hybridizing program in 1935, with the goal of developing azaleas with large blooms, cold hardy in the Washington DC area, and extending the blooming season from mid-May to mid-June. He named and registered 454 Glenn Dale cultivars, and released 440 of them beginning in 1941, with more in 1947-1949 and the last few in 1952. They range in height from 3 to 8 feet, and cover a wide range of colors, color variations, flower sizes, plant habits and bloom times.
A complete list of the Glenn Dale azaleas is shown on our Glenn Dale page. Most of the names are links to their images.
The U.S. National Arboretum has a collection of Glenn Dale images at their www.usna.usda.gov/PhotoGallery/AzaleaGallery/ page.
Russ and Velma Haag developed a long list of hybrids, as shown on our Haag Hybrid page.
The Holly Springs evergreen azalea hybrids were created by Col. Ronald C. Vines (Ret.) in Springfield, Virginia just south of Washington DC. Col. Vines (“Pete”) started his hybridizing program in 1977 “to produce azaleas with larger blooms, dwarf to mid-size growth habit and increased cold hardiness”. Descriptions from his 1990 catalog for the named hybrids are reproduced on our Holly Springs (named) page, and descriptions for the numbered hybrids which he had selected but not yet named are reproduced on our Holly Springs (numbered) page.
Pete numbers his hybrids such as HS-85-32-07, where 85 is the year he made the cross, 32 shows it was the 32nd cross made within that year, and 07 shows it was the 7th plant selected from that cross.
Little is known about the Huang evergreen azalea hybrids created by Mr. Huang because his work was done in China before their Cultural Revolution. One source of information is the documented observations of Col. Ronald C. Vines (Ret.), reproduced from his 1990 catalog on our Huang page. Col. Vines (“Pete”) feels the Huang hybrids may be the most important hybrid groups of evergreen azaleas in existence, in terms of the diverse bloom size and type, foliage and plant habit within the group.
Dr August E Kehr was a much-published plant researcher with sterling credentials. After teaching at Louisiana State University and Iowa State University, he went on to the U.S. Department of Agriculture, and to the Agricultural Research Service as scientist and administrator, and retired in 1978 to Hendersonville NC. Among his hybridizing goals were the development of yellow magnolias and a yellow evergreen azalea—and even such things as seedless pawpaws and heat-tolerant rhubarb! He also developed the technique of freezing pollen for later use, and is well known for his experimental work with chemically-induced polyploidy. Of the many hundreds of crosses he made and the many thousands of seedlings he raised, Augie registered only 11 azaleas, shown on our Kehr page.
More information about Augie and a memorial garden planted in his honor in Flat Rock, NC is shown at the www.pbase.com/kehr website.
The Robin Hill evergreen azalea hybrid group developed by Robert Gartrell is thoroughly and beautifully documented at the www.donaldhyatt.com/RobinHills/ website.
Satsuki evergreen azaleas have been hybridized in Japan for at least 500 years. There is more Satsuki information and indexes to two Satsuki Dictionaries on our Satsuki page.