Rosem Rhododendron Rhododendron catawbiense 'Roseum Elegans'

'Roseum Elegans'  is a fast growing rhododendron cultivar in the Ericaceae (blueberry) family.  This broadleaf evergreen, dense and rounded to spreading, multi-stemmed shrub has showy lavender pink flowers and glossy leaves.  The parent plant is native to the woodland slopes and ridges in the eastern United States along the Appalachian Mountain range, specifically in the Catawba region in the Blue Ridge Mountains. The genus name Rhododendron derives from the Greek words rhodo, meanin rose, and dendron, meaning tree.  

Plant this shrub in full to partial shade in acidic, rich, well-drained but moist soils. This cultivar does best in cooler climates and can struggle with our southern summers.  The root system is shallow so annual mulching will help retain moisture and keep soil temperatures even. It is important not to let the soil dry out completely or this will damage the roots. While it handles the morning sun, the plant does need protection from harsh afternoon rays and wind. It tolerates almost full shade conditions.

It typically grows from 6 to 8 feet tall and wide. It may become sparse and rangy when grown in unfavorable conditions. The plant does tolerate pruning, but keep in mind that next season's blossoms will appear on old growth.

As an evergreen it adds interest as an accent plant in winter and gardens and naturalized areas. It can be a specimen, planted in small groups or mass planted and used as a hedge or in a shrub border. 

Fire Risk: This plant has a high flammability rating and should not be planted within the defensible space of your home. Select plants with a low flammability rating for the sites nearest your home. 

Quick ID Hints:

• Long, leathery leaves, in tiers, congested at branch tips
• Large, 5-lobed bell-shaped flowers with maculations
• Terminal clusters of flowers in a raceme
• Juvenile twigs yellowish

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.

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

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. 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 catawbiense.