Mountain Azalea Rhododendron canescens

Southern pinxter azalea is a large woody, deciduous shrub in the Ericaceae (blueberry) family. This native shrub is found growing in moist woods, swamp margins, and along streams from North Carolina to Florida and west to Tennessee, Arkansas, and Texas. The genus name derives from the Greek words rhodo, which means rose, and dendron, meaning tree.  The specific epithet canescens means gray or off-white hairs refering to the hairs found on the undersides of the leaves.

Plant this azalea in moist, well-drained, acidic soil that is high in organic matter. It will not tolerate dense clay or poorly drained soil so those soils will need to be amended before planting. Ideal light requirements are dappled sunlight to partial shade. It will grow in full sun if protected from afternoon sun, which can scorch the leaves. This plant propagates slowly by root suckers and its shallow roots appreciate a yearly application of mulch.  Rabbit browsing is tolerated well.

It typically grows to 6 to 8 feet tall and less frequently may grow to 15 feet tall. It will be 6 to 10 feet wide at maturity. The leaves are thick and velvety and appear after the showy light pink flowers with very prominent stamens in the spring.  Flowers should be deadheaded after bloom. The bark is an interesting gray to reddish/brown and finely shredded. In the fall, leaves turn a burgundy red.  

Prune rhododendrons and azaleas after they bloom to preserve the current season's bloom, and allow time for the plant to produce flower buds for next year's bloom.  Rhododendrons and azaleas set next year's flower buds by mid to late summer. 

Southern pinxter azalea is ideal for a mass planting in woodland or naturalized area. Add it to a pollinator garden where its showy, fragrant flowers will attract butterflies, bees, and hummingbirds.  Or use it in a shrub border or as an attractive hedge to line a walkway.

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. 

The Clemson Cooperative Extension Home and Garden Information Center has a factsheet on common diseases of rhododendron.  

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.