Rhododendron arborescens (A)
smooth azalea
A large, upright deciduous shrub with glossy mid-green leaves turning reddish-green in autumn. Strongly-scented, funnel-shaped white, pink-flushed flowers with red stamens are borne in early summer
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Size
Ultimate height
2.5–4 metresTime to ultimate height
10–20 yearsUltimate spread
2.5–4 metresGrowing conditions
Moisture
Moist but well–drainedpH
AcidColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | White | Green | ||
| Autumn | Orange Purple Red | |||
| Winter |
Position
- Full sun
- Partial shade
Aspect
North–facing or West–facing or South–facing or East–facing
Exposure
Sheltered Hardiness
H6Botanical details
- Family
- Ericaceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Bushy
- Potentially harmful
- Harmful if eaten. Wear gloves and other protective equipment when handling. Pets (dogs, cats, rabbits, tortoises) Harmful if eaten - for further information and contact numbers regarding pets, see the HTA guide to potentially harmful plants
- Genus
Rhododendron can be evergreen or deciduous shrubs or trees, with simple leaves, sometimes with a dense colourful indumentum of hairs on the lower side, and funnel-shaped, bell-shaped or tubular flowers that may be solitary or in short racemes
- Name status
Correct
- Horticultural Group
- Azaleas can be deciduous or evergreen, with mostly small, frequently fragrant, funnel-shaped flowers in spring or early summer; deciduous azaleas often have good autumn colour
- Plant range
- Eastern N America
How to grow
Cultivation
Suitable for an open site but best grown in moist but well-drained, leafy, humus-rich acid soil in part shade with shelter; see rhododendron cultivation
Propagation
Propagate by seed when ripe, or semi-ripe cuttings in late summer, layering in autumn or grafting in late summer or late winter
Suggested planting locations and garden types
- Coastal
- Cottage and informal garden
- Hedging and screens
Pruning
Pests
May be susceptible to vine weevil, rhododendron leafhopper, pieris lacebug, scale insects, caterpillars and aphids
Diseases
May be susceptible to various Rhododendron diseases including powdery mildews, rhododendron petal blight, rhododendron bud blast, silver leaf and honey fungus
Get involved
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