JARS v53n3 - New Azaleas Extend Blooming Season to Autumn

New Azaleas Extend Blooming Season to Autumn
Robert Edward Lee
Independence, Louisiana

Aimee Coker
Bushnell, Florida

Reprinted from the September 1998 issue of Landscape & Nursery Digest, formerly published by Betrock Information Systems, Inc. The article appeared under the title "Azaleas."

Azaleas have been admired and enjoyed for many centuries. The first reported plants grew wild on the islands of Japan. In the late sixteenth century, early traders from the Western world (the English and Dutch) were captivated by the beauty of the azalea bloom. This quickly lead to the exportation and spread of early azalea varieties from Japan to Europe and then eventually to America. Today, in the United States azaleas are still admired for their spectacular blooms and are popular in the North Pacific and Southeastern regions of the country. The only slight drawback to an otherwise exceptional plant group is their brief blooming period. In pursuit of a longer blooming azalea a new class of azalea has recently been developed - the Encore Azalea®.

The Encore Azalea® is an exciting group of spring, summer, and fall flowering evergreen azaleas that have recently been released to the public. Robert Edward Lee and Flowerwood Nursery have worked together to bring this revolutionary group of plants to the market. The diversity within this group yields a wide range of growth and color characteristics.

The Encore Azaleas® vary in size from dwarf compact forms to large background plants in shades of pink, orange, and lavender. It was Lee's dream to recreate the beauty of spring flowering azaleas in other times of the year that lead to this creation.

Encore Azalea® 'Autumn Embers'
Encore Azalea® 'Autumn Embers
in the landscape.
Photo courtesy of the Flowerwood Nursery

Robert Lee developed an admiration for plants at an early age. In high school Lee worked at a wholesale nursery that specialized in azaleas. This is when he began to notice the wide variation between different azalea varieties and then began to focus on developing new azalea varieties by selecting vegetative sports (mutations). A few of these selections were nice; however, Lee soon realized that if he wanted to make a significant change in new azalea varieties, he would have to venture into plant breeding.

On one hot July day, when Lee was visiting a friend he had met through the Azalea Society of America, he came upon a small tray of the previous year's rooted cuttings in full bloom. These were cuttings from Rhododendron oldhamii and the friend offered them to Lee to take home. The little plants thrived and bloomed off and on until frost. The bloom buds developed on new vegetative growth and opened as soon as they matured. Other bloom buds were in different stages of development as the plant stems continued to grow.

After observing the unique flowering characteristics of Rhododendron oldhamii , Lee immediately started thinking of the possibilities of crossing this special plant with other azaleas. Would it be possible to create a new group of azaleas with multiple blooming times with a wide range of color and growth habits that would be as easy to take care of as the old standard varieties? With this question Lee began the work that led to a whole new revolutionary group of azaleas.

This hybridization process started with selecting azalea varieties with fall blooming tendencies to be the seed parent plant. When the plant started blooming, a flower would be emasculated to prevent self-pollination. To prevent cross-pollination from other azaleas' pollen, a brown paper bag was used to cover the flower. After a couple of days the bag would be removed so that the Rhododendron oldhamii pollen could be applied. The pollen used was either gathered from fresh flowers or ones that had been previously dried and stored in a refrigerator. The bag would be placed back over the pollinated flower for a couple of days and then removed.

When pollination was successful, a delicate seedpod would begin to form and continue to mature for four to six months. Then the seedpods were carefully harvested, dried, and stored. In late March or April of the following year, seeds were sown in trays filled three-quarters with medium sized pine bark and then a top layer of water saturated peat moss. The peat moss surface was flattened out so that the azalea seeds could be lightly sprinkled over the level surface. The seeds were watered with mist spray nozzle, taking care not to over water or not to let the peat moss dry out. Soon the seeds started to germinate (14-28 days) and grow. This was a crucial time to control insects, disease, and other pests from destroying the tender plants. After about six months when the seedlings began to reach about a half an inch tall they were potted into liner trays. Eight months to a year later when the seedlings reached 2-6 inches tall they were then potted into 4-inch containers. Within another 8 to 12 months the seedlings were repotted into 6-inch containers.

When the young plants started blooming, they performed far beyond what Lee had expected. The breeding program had become quite large and Lee was concerned as to how he could properly select from so many plants. In 1992, an agreement was made with Flowerwood Nursery to continue this program and to select out the best commercial varieties from these seedlings.

In 1993 approximately 7,500 seedlings were moved to Flowerwood Nursery's Loxley operation and potted into 12-inch containers. Selections have been ongoing and based on such attributes as flowering characteristics, growth habit, foliage quality, disease resistance, and ease of production. Over the next four years the focus group has gone from the original 7,500 seedlings to the first 12 named varieties. Presently 14 plant selections are in the process of being patented and it is anticipated that an additional 24 selections could be developed into cultivars over the next 10 years. Lee's breeding program has resulted in the birth of the Encore Azalea®.

Some of the new named varieties include: Encore Azalea® 'Autumn Royalty' 1 with rich purple blooms, Encore Azalea® 'Autumn Embers' 1 with a low, spreading growth habit and orange-red flowers, Encore Azalea® 'Autumn Cheer' 1 with a compact growth habit and deep pink flowers, and Encore Azalea® 'Autumn Bravo' 1 * with an upright habit and bright red flowers.

Other named varieties include 'Autumn Amethysts/Autumn Rouge' 1 , 'Autumn Coral' ', and 'Autumn Monarch' 1 .

Evergreen azaleas such as the Encore Azaleas® can be a wonderful landscape choice because they are easily maintained and are consistent performers. Azaleas come in a multitude of sizes and colors and therefore adaptable to many different planting situations. Cultural requirements for azaleas include well drained, slightly acidic soil with light shade or afternoon shade. The optimal time to prune and fertilize established azaleas is after their spring blooming season.

Encore Azaleas® are being evaluated and are on display at some of the most prestigious locations and botanical gardens throughout the country. It has been predicted that the Encore Azalea® will redefine the world of evergreen azaleas with their multiple flowering capacity.

Robert Lee is a member of the American Rhododendron Society. Aimee Coker represents Flowerwood Nursery, Inc., of Bushnell, Florida.

1 Plant patent applied for (PPAF)

* Name is unregistered.

Encore Azaleas® - Autumn Series

Encore Azalea® 'Autumn Rouge' (PP#10438)

'Autumn Rouge' is the breeder's favorite. It is very prolific, flowering from early July through the fall. The blooms are semi-double and are strong pink, almost red in color. This azalea tends to grow upright.

Encore Azalea® 'Autumn Royalty' (PP#10580)

This variety is robust. The shrub is upright and globose. The foliage is large and dark green. The flowering period is from late July to frost. The blooms are large single and rich purple in color.

Encore Azalea® 'Autumn Royalty'
Encore Azalea® 'Autumn Royalty'
Photo courtesy of the Flowerwood Nursery

Encore Azalea® 'Autumn Coral' (PP#10568)

This plant growth habit is mounding. It blooms abundantly from July through the fall. Flowers are salmon pink with prominent fuchsia flecking and medium in size.

Encore Azalea® 'Autumn Coral'
Encore Azalea® 'Autumn Coral'
Photo courtesy of the Flowerwood Nursery

Encore Azalea® 'Autumn Embers' (PP#10581)

The growth habit is low, spreading and dense. The foliage is dark green. Flowering is from early July through the fall and very intense. Blooms are single and semi-double and are deep orange red in color. Unbelievable quantities of fall flowering.

Encore Azalea® 'Autumn Amethyst' (PP#10567)

This variety is the most cold hardy of the Autumn Series. The foliage is elongated, pointed and rough in texture. The leaves take a beautiful dark cast in the winter. The blooms are soft purple. The growth habit is intermediately dense and spreading. Flowering begins early September.

Encore Azalea® 'Autumn Cheer' (PP#10579)

Foliage, growth habit and flowers look like a Kurume-type azalea. Flowers are slightly larger than Kurume flowers and are deep pink. This variety is the most compact of the autumn cultivars. Flowering is from early August through the fall.

Encore Azalea® 'Autumn Monarch' (PPAF)

'Autumn Monarch' has beautiful semi-double coral blooms. These blooms are highlighted with deep reddish purple flecking and tend to be slightly ruffled. This upright grower has bright green elliptical leaves. Average dimensions are 4' x4' wide.

Encore Azalea® 'Autumn Bravo'* (PPAF)

'Autumn Bravo' produces strong, bright red, single to semi-double, 2-inch blooms. This full upright grower features large rich green oval foliage. Average dimensions are 4' x 4' wide.

Encore Azalea® 'Autumn Bravo'*
Encore Azalea® 'Autumn Bravo'*
Photo courtesy of the Flowerwood Nursery

Public Viewing
The Encore Azaleas® have been placed in the following public gardens:
Atlanta Botanical Garden, Atlanta, Georgia
Birmingham Botanical Gardens, Birmingham, Alabama
Callaway Gardens, Pine Mountain, Georgia
Dallas Horticulture Center in Fair Park, Dallas, Texas
Memphis Botanic Garden, Memphis, Tennessee
Mobile Botanical Gardens, Mobile, Alabama