News Release Distributed 11/05/10
By LSU AgCenter Horticulturists Dan Gill, Kyle Huffstickler and Allen Owings Some of the most popular plants being sold in Louisiana these days are Encore azaleas.
These multiseasonal blooming azaleas debuted in the late 1990s and have tendencies to bloom during spring, summer and fall. More than 20 varieties of Encore azaleas are now on the market, and home gardeners can select varieties for small, intermediate and large growth habits.
Azaleas perform best in full sun to light, filtered shade. In Louisiana, most azaleas prefer morning sun with afternoon filtered shade. At least four to six hours of direct sunlight per day are required for good flowering. But care must be taken to prevent exposure to drought or other heat-related stress conditions associated with full-sun exposure.
Too much shade, however, can result in skipped or significantly reduced bloom cycles. Typically, the more sun azaleas are exposed to, the more problems you may have with azalea lace bugs. But we are fortunate that Encore azaleas are less susceptible to these major pests than other azalea groups.
A raised bed is needed to grow azaleas most successfully. Make sure you know the pH of both your native soil and the landscape bed amendment material you use to make the raised bed. Azaleas prefer a soil pH of 5.5. A soil pH above 6.5 presents problems for azaleas. Larger-growing Encore azaleas establish better than smaller- and intermediate-growing Encores in adverse soil pH conditions.
Water azaleas well when you first plant them and keep the soil moist but never wet. Newly planted azaleas will die quickly if the soil dries excessively. Azaleas should not need regular watering after the first year, however, unless there are periods of excessive drought.
Fertilize these plants with the label-recommended levels of a slow-release fertilizer in spring after flowering is complete. Ironite or other fertilizers with micronutrients may help azaleas keep a greener color. Light fertilization also may be needed in mid- to late summer.
We are in the prime months for planting azaleas. Encores do best when planted during the fall. Garden centers have the most azaleas available in spring, but fall is the best time for planting to help the plants get established in the landscape. New roots produced in the fall will help the azalea flourish during the next growing season.
Although less watering is necessary now, don’t allow the roots to become dry. A 2- to 3-inch layer of pine straw is an excellent mulch material and will aid in weed suppression.
There are always questions about when to prune the multiseasonal blooming azaleas. Most require very little pruning to retain good form and do not need "dead-heading." If you think your azaleas need pruning, do so immediately – or within a month – after spring flowering for maximum bud set. Light pruning of established plants will stimulate growth and flowering.
Encore azaleas are great plants for Louisiana landscapes. These varieties offer more flower colors now than when the first few varieties were released. You can find reds, oranges, pinks, blushes, whites, lavenders and others.
Are you ready to select Encore varieties?
For lace bug resistance, try Autumn Amethyst, Autumn Royalty, Autumn Cheer, Autumn Twist, Autumn Sangria and Autumn Rouge.
For moderate lace bug resistance, you can consider Autumn Embers, Autumn Starlite, Autumn Princess, Autumn Brave and Autumn Ruby.
The most cold-hardy Encore azaleas are Autumn Amethyst, Autumn Royalty, Autumn Sunset, Autumn Carnation, Autumn Ruby, Autumn Twist, Autumn Cheer, Autumn Sangria, Autumn Lilac and Autumn Sundance.
The largest-growing varieties are Autumn Belle, Autumn Monarch, Autumn Moonlight, Autumn Royalty, Autumn Sangria and Autumn Twist.
Medium-size plants are Autumn Amethyst, Autumn Carnation, Autumn Carnival, Autumn Debutante, Autumn Embers, Autumn Empress, Autumn Rouge, Autumn Starlite, Autumn Sundance, Autumn Sunset and Autumn Sweetheart.
The smallest-growing varieties are Autumn Angel, Autumn Bravo, Autumn Cheer, Autumn Chiffon, Autumn Coral, Autumn Princess and Autumn Ruby.
Many groups of azaleas flower during both spring and fall in Louisiana. In addition to the Encores, you also can select varieties belonging to the Robin Hill, Satsuki and GlennDale groups.
Fall is the best time to get them established, too, so do some azalea planting during the next month or so.
Visit LaHouse in Baton Rouge to see sustainable landscape practices in action. The home and landscape resource center is near the intersection of Burbank Drive and Nicholson Drive (Louisiana Highway 30) in Baton Rouge, across the street from the LSU baseball stadium. For more information, go to www.lsuagcenter.com/lahouse and www.lsuagcenter.com/lyn.
Rick Bogren