Rhododendron Encore® Group

Encore® azaleas are a group of cultivars of evergreen shrubs in the Ericaceae (blueberry) family that typically grow 2 to 5 feet tall and 3 to 4 feet wide. These cultivars bloom not only in the spring but also in the summer and fall, hence the name encore. The genus name derives from the Greek words rhodo, which means rose, and dendron, meaning tree.

Though many azaleas require shade, Encore® azaleas do well in sunny locations of the landscape as well as partial or dappled shade from an overhead canopy of trees. For the best blooms, plant in a location that receives 4 to 6 hours of sun with afternoon shade. Plant in well draining, moist, acidic soils that have a high organic content and be sure to water regularly.  Add a 3 inch layer of organic mulch each winter to protect the root zone from freezing. These low maintenance shrubs require very little pruning and no deadheading.

There are two sizes—dwarf and intermediate—and they come in a variety of colors from white, to pinks, purples, and reds. The dwarf cultivars reach a maximum height of 3 1/2 feet and make a good choice for the middle of a border. Intermediate cultivars reach a height of 5 feet tall and are more suitable for the backs of borders. These showy shrubs also work very well as a specimen in a container and can add color and interest to the understory of a woodland garden or naturalized area. Utilize their diminutive height as a low hedge or planted along a foundation where their blooms can be enjoyed from a window.  Butterflies and hummingbirds are attracted to the blooms, so plant them near a patio, pool, or walkway where the wildlife show is best enjoyed.

Insects, Diseases, and Other Plant Problems: Insect problems include aphids, borers, lace bugs, leafhoppers, mealybugs, mites, nematodes, scale, thrips, and whitefly. Diseases include canker, crown rot, root rot, leaf spot, rust, and powdery mildew. This plant is frequently damaged by deer.

While these shrubs remain very popular for landscape use, many cultivars are susceptible to Phytophthora root rot– this leads to leaf loss, reduced vigor, branch dieback, and wilting.  Implement good cultural practices first, such as improving drainage with organic matter or berms and avoiding overwatering or overfertilization.  However, if you have a site with a history of this disease, consider planting one of the root rot-resistant alternative species listed in the left-hand sidebar.

Many Rhododendron cultivars are susceptible to Phytophthora root rot. For suitable alternatives, see this video created by Charlotte Glen as part of the Plants, Pests, and Pathogens series. 

VIDEO Created by Elizabeth Meyer for "Trees, Shrubs and Conifers" a plant identification course offered in partnership with Longwood Gardens.

More information on Rhododendron.