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Kaempferi Azalea

Rhododendron kaempferi (rho-doh-DEN-dron KAYMP-fer-ee)

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

Torch azalea is a woody, evergreen to semi-evergreen shrub in the Ericaceae (blueberry) family. Found growing in the mountainous regions and grassy hills of Japan. The genus name derives from the Greek words rhodo , which means rose, and dendron , meaning tree. This erect multistemed shrub has an dense rounded canopy and can grow from 4 to 10 feet tall and 5 to 6 feet wide in about 10 years. Plant in partial to dappled shade with up to 4 hours of sun. While plants may flower better with more sun, it becomes difficult to maintain their water needs and they can burn. They need moist well-drained rich acidic soils, avoiding poorly drained soils. If this is not possible consider planting in a raised bed. Torch azalea will need some protection from cold so plant it in a sheltered location in the landscape. Propagate this plant through stem cuttings. The leaves are evergreen in mild climates and semi-evergreen in areas with cold winters and they provide attractive fall color. Showy salmon pink to rose red flowers appear late spring to early summer and are one of the few shade flowering evergreen shrubs. Low maintenance and easy to grow. This shrub is less demanding than Kurume azaleas ( Rhododendron ponticum ). It is the parent plant to many evergreen azaleas. It works well in a woodland, naturalized area, or Asian garden, planted in a container, window box or near a shaded patio or walkway where the blooms can be enjoyed. It can be grown as a houseplant. This plant is often browsed by deer and rabbits, especially new growth, so may need protection. Insects, Diseases, and Other Plant Problems: Rhododendrons are susceptible to insect and disease 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. Full sun can scorch the leaves and the roots rot if the soil does not drain well. A healthy plant in the right place with proper maintenance should have few problems. This plant is frequently damaged by deer. 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, 64 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

Full plant profile

Growing Conditions
Plant type
Poisonous; Shrub
Life cycle
Woody
USDA zones
5a, 5b, 6a, 6b, 7a, 7b
Light
Dappled Sunlight (Shade through upper canopy all 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
3 feet-6 feet; 6-feet-12 feet
NC region
Coastal; Piedmont
Mature size
Height: 4 ft. 0 in. - 10 ft. 0 in. | Width: 5 ft. 0 in. - 6 ft. 0 in.
Maintenance
Low
Canopy layer
3 - Shrub (3-15 ft)
Form & Appearance
Habit / form
Dense; Erect; Multi-stemmed; Rounded
Texture
Medium
Foliage
Semi-evergreen
Leaf color
Gold/Yellow; Green
Leaf type
Simple
Leaf arrangement
Alternate
Leaf shape
Elliptical; Lanceolate
Leaf margin
Entire
Leaf feel
Glossy
Leaf size
1-3 inches long, 1-3 inches wide
Hairs present
Yes
Leaf detail
Simple, alternate, glossy dark green above lighter below lanceolate to elliptic leaves 2" long 1 1/8" wide with smooth margins; reddish fall color. Spring leaves are decidious, summer leaves are evergreen or deciduous depending on winter temperatures. Petioles have dense brown hairs, as do both sides of the leaf especially at the midrid.
Fall color
Red/Burgundy
Flower color
Gold/Yellow; Orange; Pink; Red/Burgundy; White
Flower value
Showy
Flower form
Raceme
Flower shape
Funnel
Flower size
1-3 inches
Flower detail
2 to 3 flowers in a terminal raceme Salmon-red, orange-red, pink to rosy scarlet and white 5 petaled 1 1/2'"-2" across funnel shaped flowers appear late spring to early summer.
Bloom time
Spring; Summer
Fruit type
Capsule
Stem detail
Dense flattend forward pointing red-brown hairs.
Wildlife & Ecology
Native status
Non-native
Origin
Japan
Wildlife value
Nectar from flowers attracts hummingbirds and bees. Members of the genus Rhododendron support the following specialized bee: Andrena (Andrena) cornelli.
Attracts
Hummingbirds; Pollinators; Specialized Bees
Food & Medicine
Fruit type
Capsule
Landscape Use
Landscape location
Container; Naturalized Area; Patio; Walkways; Woodland
Landscape theme
Asian Garden
Design feature
Mass Planting; Small groups
Garden tags
#deciduous #specialized bees #hummingbird friendly #evergreen #nectar plant #pollinator plant #problem for cats #problem for dogs #problem for horses #bee friendly #easy to grow #flowers late spring #flowers early summer #showy flowers #low maintenance #Asian garden #deer browsing plant #container plant #spring flowers #rabbit browsing plant #shade flowers #semi-evergreen #poisonous #patio #wildlife friendly #woodland #walkway
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; Pests of Azalea
Disease problems
Southern Blight of Herbaceous Ornamentals
Problems
Poisonous to Humans; Problem for Cats; Problem for Dogs; Problem for Horses
Propagation
Stem Cutting
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.