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Royal Azalea

Rhododendron schlippenbachii (rho-doh-DEN-dron shlip-pen-BAH-kee-eye)

Family: Ericaceae Non-native Shrub (3-15 ft)

Royal azalea is a woody, upright, rounded, deciduous shrub in the Ericaceae (blueberry) family. It is native to China, Japan, and Korea. Growing 6 to 8 feet tall and wide, its showy, fragrant flowers appear in April to May. The species epithet honors Baron von Schlippenbach, who first brought this plant to the attention of botanists. Although royal azalea will grow in full sun, it prefers dappled sun or high open shade and moist, well-drained, acidic, humus-rich soil. It does not tolerate dense clay, so if you have clay soil, amend with organic material. The roots may rot if soil does not drain well. Plant the root ball high in the soil to help with drainage issues. Pruning, if desired, may be done after flowering. Site this plant in a woodland or natural area. With its large size and showy flowers, it can be used as a dramatic specimen. Its flowers will also attract bees, butterflies, and other pollinators to a pollinator garden. 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 tolerates browsing by rabbits but 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. 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 .

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 57 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.

Fills a similar niche Rhododendron Rhododendron minus var. chapmanii Rhododendron yakushimanum
Similar, less problematic Abelia x grandiflora Camellia sasanqua Rhaphiolepis indica Rhaphiolepis x delacourii

Full plant profile

Growing Conditions
Plant type
Perennial; Poisonous; Shrub
Life cycle
Woody
USDA zones
4a, 4b, 5a, 5b, 6a, 6b
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; Loam (Silt); Sand
Soil pH
Acid (<6.0)
Soil drainage
Good Drainage | Moist
Available space
6-feet-12 feet
NC region
Mountains
Mature size
Height: 6 ft. 0 in. - 8 ft. 0 in. | Width: 6 ft. 0 in. - 8 ft. 0 in.
Maintenance
Low
Canopy layer
3 - Shrub (3-15 ft)
Form & Appearance
Habit / form
Rounded
Texture
Medium
Foliage
Deciduous
Leaf color
Green
Leaf type
Simple
Leaf arrangement
Alternate; Whorled
Leaf size
3-6 inches long
Hairs present
No
Leaf detail
Alternate, simple dark green leaves; 2 to 5.5 in. long; appears whorled
Flower color
Pink
Flower value
Fragrant; Showy
Flower form
Raceme
Flower shape
Funnel
Flower size
1-3 inches
Flower detail
2 to 3 in. flowers in late spring to early summer; pale to rose pink; fragrant; open as leaves emerge
Bloom time
Spring; Summer
Fruit type
Capsule
Wildlife & Ecology
Native status
Non-native
Origin
China, Japan, Korea
Wildlife value
Flowers attract butterflies. Members of the genus Rhododendron support the following specialized bee: Andrena (Andrena) cornelli. This plant tolerates browsing by rabbits.
Attracts
Butterflies; Pollinators; Specialized Bees
Food & Medicine
Harvest time
Fall
Fruit type
Capsule
Landscape Use
Landscape location
Container; Naturalized Area; Woodland
Landscape theme
Butterfly Garden; Pollinator Garden
Design feature
Specimen
Garden tags
#showy flowers #deciduous #specialized bees #fragrant flowers #nectar plant #rabbit resistant #pollinator plant #problem for dogs #problem for horses #problem for cats #bee friendly #specimen #naturalized area #poisonous #container plant #wildlife friendly #woodland
Problems & Resistance
Insect problems
Azalea Lace Bug; Azalea Plant Bug; Azalea Caterpillar; Azalea Leafminer; Azalea Stem Borer; Azalea Bark Scale; Azalea Whitefly; Arthropod Pests of Azalea; Azalea Pest Management Calendar; Pests of Azalea
Disease problems
Southern Blight of Herbaceous Ornamentals
Problems
Poisonous to Humans; Problem for Cats; Problem for Dogs; Problem for Horses
Resistant to
Rabbits
Poison severity
Low
Poison parts
Bark; Flowers; Fruits; Leaves; Roots; Sap/Juice; Seeds; 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; Roots; Sap/Juice; Seeds; Stems

Planted at Hunnicutt

Nobody’s planted this one yet.