Years of trials in botanical gardens, university trials and plant nurseries have yielded important new cold-hardy findings about Encore Azaleas, according to Kip McConnell, director of Plant Development Services, Inc. The studies reveal that nineteen varieties of Encore Azalea are cold hardy to USDA Zone 6B and 10 of those varieties are cold hardy to USDA zone 6A.
“These findings significantly expand the accepted growing areas for Encore Azaleas,” says McConnell. “For years, garden centers and home gardeners in these zones have told us about their success with many of our varieties during cold weather and now these findings confirm their cold-hardiness. Years of research confirm that even more gardeners can now enjoy Encore Azaleas since these varieties continue to thrive, even through winter freezing.”
Ten varieties consistently exhibited cold hardiness throughout Zones 6A and 6B:
- Autumn Amethyst
- Autumn Carnation
- Autumn Cheer
- Autumn Lilac
- Autumn Royalty
- Autumn Ruby
- Autumn Sangria
- Autumn Sundance
- Autumn Sunset
- Autumn Twist
In Zone 6B, nine additional varieties also consistently exhibited solid cold hardiness:
- Autumn Bravo
- Autumn Carnival
- Autumn Debutante
- Autumn Embers
- Autumn Empress
- Autumn Monarch
- Autumn Princess
- Autumn Sweetheart
- Autumn Rouge
For best results in Zones 6B and colder, gardeners should plant in spring or early summer. In zones 7-9, Encore Azaleas benefit from fall and late-summer planting schedules. Encore Azaleas may need special care in zones colder than 6A, but their multi-season blooms make them ideal for container gardens. As a base plant in a container garden, Encore Azaleas can be paired with seasonal favorites, and then moved inside when a winter freeze threatens.
Encore Azaleas begin blooming each spring like a traditional azalea. Once this initial blooming concludes, new shoots begin to grow and set buds. Blooms emerge again in mid-summer and continue in many areas until first frost; that’s something no other azalea can consistently do. Today, the 25 varieties of Encore Azalea offers a growth habit and bloom color for every landscape. The evergreen shrubs enjoy more sun than traditional azaleas, but offer the same easy care.
Encore Azaleas are the invention of plant breeder Robert E. “Buddy” Lee of Independence, Louisiana. PDSI, based in Loxley, Ala., assisted Lee in the 15-year hybridization and selection process, and now manages the wholesale grower group that brings Encore Azaleas to gardeners across the Southeast, Mid-Atlantic, Northeast, Northwest and California.
For more on Encore Azalea varieties and their USDA zone hardiness, please visit www.EncoreAzalea.com.
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