Rhododendron arboreum
tree-like rhododendron
A large, narrow, evergreen tree, with dark green leaves, to 20cm long, a smooth cinnamon-brown, fawn or silvery indumentum on the undersides. Flowers, produced in rounded trusses in early spring, are up to 5cm long and may be red, white or any shade of pink, usually with spotting in the throat
Size
Ultimate height
8–12 metresTime to ultimate height
20–50 yearsUltimate spread
2.5–4 metresGrowing conditions
Moisture
Moist but well–drainedpH
AcidColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Pink Red White | Green Grey Silver Brown | ||
|---|---|---|---|---|
| Summer | Green Grey Silver Brown | |||
| Autumn | Green Grey Silver Brown | |||
| Winter | Green Grey Silver Brown |
Position
- Partial shade
Aspect
South–facing or North–facing or West–facing or East–facing
Exposure
Sheltered Hardiness
H4Botanical details
- Family
- Ericaceae
- Native to GB / Ireland
- No
- Foliage
- Evergreen
- Habit
- Columnar upright
- 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
- Plant range
- India & Sino-Himalaya
How to grow
Cultivation
Grow 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
- Architectural
- Cottage and informal garden
- Low Maintenance
Pruning
Pests
May be susceptible to vine weevil, rhododendron and azalea whitefly, 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
The Royal Horticultural Society is the UK’s leading gardening charity. We aim to enrich everyone’s life through plants, and make the UK a greener and more beautiful place.