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Exbury Azaleas

Rhododendron (roh-do-DEN-dron)

Family: Ericaceae Unknown Shrub (3-15 ft)

Exbury azaleas are deciduous shrubs in the Ericaceae (blueberry) family. Exbury azaleas have an upright, open spreading habit. Large showy flower trusses explode in the spring with a wide variety of vibrant colors. The flowers are similar to the flame azalea. The showy leaf color provides fall interest. These plants prefer moist, well-drained, acidic soils in dappled shade and protection from afternoon sun which can scorch the leaves. They do 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. Avoid overwatering and over-fertilizing. They are very winter hardy and have a moderate growth rate. Pruning, if desired, may be done after flowering. These shrubs are excellent for naturalizing and are at home as understory shrubs planted in groups in woodland gardens, or as specimens in pollinator gardens where the flowers will attract hummingbirds and bees. 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. 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, 58 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
Fills a similar niche Rhododendron canescens Rhododendron minus var. chapmanii Rhododendron periclymenoides

Full plant profile

Growing Conditions
Plant type
Poisonous; Shrub
Life cycle
Woody
USDA zones
5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
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
Clay; High Organic Matter; Loam (Silt); Sand
Soil pH
Acid (<6.0)
Soil drainage
Good Drainage | Moist
Available space
6-feet-12 feet
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 4 ft. 0 in. - 8 ft. 0 in. | Width: 4 ft. 0 in. - 8 ft. 0 in.
Growth rate
Medium
Maintenance
Medium
Canopy layer
3 - Shrub (3-15 ft)
Form & Appearance
Habit / form
Erect; Open; Spreading
Texture
Medium
Foliage
Deciduous
Leaf color
Green
Leaf type
Simple
Leaf arrangement
Alternate
Leaf shape
Elliptical; Oblong
Leaf margin
Entire
Leaf value
Showy
Leaf size
3-6 inches long
Hairs present
No
Leaf detail
Simple elliptic to oblong alternate leaves 2 to 6 inches long with entire margins. May have bronze tinge; good fall color of red, orange, yellow or bronze.
Fall color
Brown/Copper; Gold/Yellow; Orange; Red/Burgundy
Flower color
Gold/Yellow; Orange; Pink; White
Flower value
Fragrant; Showy
Flower form
Raceme
Flower shape
Trumpet
Flower detail
Flowers are trumpet shaped with five petals born in trusses of 18 to 30 blooms. Individual flowers come in a wide range of colors from reds, oranges, yellows and white. They are large and showy, lightly fragrant and bloom from early to late spring.
Bloom time
Spring
Fruit type
Capsule
Wildlife & Ecology
Native status
Unknown
Wildlife value
Excellent nectar plant for bees, hummingbirds and butterflies. Members of the genus Rhododendron support the following specialized bee: Andrena (Andrena) cornelli.
Attracts
Butterflies; Hummingbirds; Pollinators; Specialized Bees
Food & Medicine
Fruit type
Capsule
Landscape Use
Landscape location
Rock Wall
Landscape theme
Rock Garden
Design feature
Border; Small groups; Specimen
Garden tags
#showy flowers #deciduous #specialized bees #hummingbird friendly #nectar plant #naturalizes #pollinator plant #butterfly friendly #problem for dogs #problem for horses #problem for cats #bee friendly #fall color bronze #flowers late spring #deciduous shrub #rock garden #flowers early spring #fall color yellow #specimen #flowers mid-spring #deer resistant #fragrant flowers #fall color red #fall color orange #poisonous #wildlife friendly #HS111 #HS304 #shrub border
Problems & Resistance
Insect problems
Azalea Lace Bug; Azalea Plant Bug; Azalea Caterpillar; Azalea Leafminer; Azalea Stem Borer; Azalea Bark Scale; Azalea Whitefly; Azalea Pest Management Calendar; Azalea Pest Management Calendar
Problems
Poisonous to Humans; Problem for Cats; Problem for Dogs; Problem for Horses
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.