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Cumberland Azalea

Rhododendron cumberlandense (roh-do-DEN-dron kum-ber-land-DEN-see)

Family: Ericaceae Native Shrub (3-15 ft)

Cumberland azalea is a woody, deciduous shrub in the Ericaceae (blueberry) family. It is native to the southeastern United States, specifically the Cumberland Plateau of Kentucky south to Tennessee and the mountains of Georgia, Alabama, and North Carolina. It grows 3 to 7 feet tall. The genus name derives from the Greek words rhodo , which means rose, and dendron , meaning tree. This azalea prefers full sun in the north and partial shade in the south and will need supplemental water during a drought. Plant in organically-rich, moist, well-drained, acidic soil and only prune lightly. It is best propagated from seed as it is difficult to start from cuttings. Flowers are showy in orange or pink colors and bloom from June to July after the plant has leafed out which is later than other azaleas. 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. Use in woodland and native gardens as a specimen or in small groups. It works well planted on slopes or banks. Since it is attractive to hummingbirds, butterflies, and moths it makes a good border shrub in butterfly and pollinator gardens. It is a host plant for the larvae of the Rhododendron borer moth ( Synanthedon rhododendri ) as well as the Azalea caterpillar ( Datana major ) . Quick ID Hints: Green ovate leaves 1 to 3 inches in length Hairs may be present on the leaf margins Bark is brownish gray smooth to vertically furrowed and shredding Insects, Diseases, and Other Plant Problems: While azaleas and rhododendrons 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. For suitable alternatives, see this video created by Charlotte Glen as part of the Plants, Pests, and Pathogens series. The Clemson Cooperative Extension Home and Garden Information Center has a factsheet on common diseases of rhododendron. VIDEO Created by Elizabeth Meyer for " Trees, Shrubs and Conifers " a plant identification course offered in partnership with Longwood Gardens. More information on Rhododendron .

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 67 attributes.

How it fits the guild

Guild layer 3 - Shrub (3-15 ft) Optimal soil pH Acid (<6.0)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Often confused with Rhododendron calendulaceum Rhododendron 'Stonewall Jackson'
Similar, less problematic Abelia x grandiflora Camellia sasanqua Rhaphiolepis indica Rhaphiolepis x delacourii

Full plant profile

Growing Conditions
Plant type
Native Plant; Poisonous; Shrub
Life cycle
Woody
USDA zones
5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b
Light
Full sun (6 or more hours of direct sunlight a day) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
High Organic Matter
Soil pH
Acid (<6.0)
Soil drainage
Moist
Available space
6-feet-12 feet
NC region
Mountains; Piedmont
Mature size
Height: 3 ft. 0 in. - 7 ft. 0 in. | Width: 3 ft. 0 in. - 6 ft. 0 in.
Growth rate
Slow
Maintenance
Low
Canopy layer
3 - Shrub (3-15 ft)
Form & Appearance
Habit / form
Erect; Spreading
Foliage
Deciduous
Leaf color
Green
Leaf type
Simple
Leaf arrangement
Alternate
Leaf shape
Obovate; Ovate
Leaf margin
Entire
Leaf size
1-3 inches long, < 1 inch wide
Hairs present
Yes
Leaf detail
Ovate to obovate green leaves are up to 3 inches long, apex acute to obtuse, and a few hairs may be present on the margins.
Flower color
Orange; Pink
Flower value
Showy
Flower shape
Funnel
Flower size
1-3 inches
Flower detail
Yellow-orange to deep red flowers are up to 1.75 inches across in clusters of 3-7. They are funnel-shaped with 5 spreading lobes and exerted stamens and stigma. Hairs are present on the outer surface. Bloom from June to July after the plant has leafed out.
Bloom time
Summer
Fruit type
Capsule
Fruit detail
Displays from July to October.
Bark color
Dark Brown; Dark Gray
Bark detail
The bark is brownish gray, smooth to vertically furrowed and shredding.
Stem color
Brown/Copper
Stem detail
Young twigs are pubescent with non-glandular hairs
Wildlife & Ecology
Native status
Native
Origin
Southeastern U.S.A.
Distribution
AL , GA , KY , NC , SC , TN , VA
Wildlife value
Larval host for butterflies and moths.
Attracts
Butterflies; Hummingbirds; Moths; Pollinators; Small Mammals
Host plant for
butterflies and moths
Food & Medicine
Harvest time
Fall; Summer
Fruit type
Capsule
Landscape Use
Landscape location
Slope/Bank; Woodland
Landscape theme
Butterfly Garden; Native Garden; Pollinator Garden
Design feature
Border; Small groups; Specimen
Garden tags
#deciduous shrub #deciduous #NC native #native shrub #moth caterpillar host #food source herbage #food source nectar #mammals #food source pollen #hummingbird friendly #food source summer #food source fall #butterfly friendly #pollinator plant #problem for cats #problem for dogs #problem for horses #Audubon #red flowers #orange flowers #specimen #slopes #poisonous #moth friendly #woodland #butterfly caterpillar host #shrub border #small groups
Problems & Resistance
Insect problems
Arthropod Pests of Azalea; Azalea Pest Management Calendar; Azalea Lace Bug; Azalea Plant Bug; Azalea Caterpillar; Azalea Leafminer; Azalea Stem Borer; Azalea Bark Scale; Azalea Whitefly
Disease problems
Southern Blight of Herbaceous Ornamentals
Problems
Poisonous to Humans; Problem for Cats; Problem for Dogs; Problem for Horses
Propagation
Seed
Poison severity
Low
Poison parts
Bark; Flowers; Fruits; Leaves; Sap/Juice; Stems
Poison symptoms
While the plants are known to contain toxins, ingestion of moderate amounts of azalea (nectar or leaves) poses little toxic hazard.
Toxic principle
Grayanotoxins
Contact dermatitis
No
Toxicity summary
Low severity poison; parts: Bark; Flowers; Fruits; Leaves; Sap/Juice; Stems

Planted at Hunnicutt

Nobody’s planted this one yet.