Rhododendron molle subsp. japonicum (M)
Japanese azalea
A deciduous azalea up to 2m high, with an upright habit, and green leaves that are softly hairy underneath. Young shoots and flower buds also have a covering of fine downy hairs. Flowers are produced before the leaves in spring, and are scented, broadly funnel-shaped, and usually shades of orange or coral red. Leaves are often richly coloured in autumn
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Size
Ultimate height
1.5–2.5 metresTime to ultimate height
5–10 yearsUltimate spread
1.5–2.5 metresGrowing conditions
Moisture
Moist but well–drainedpH
AcidColour & scent
Stem | Flower | Foliage | Fruit | |
Spring | Orange Yellow | Green | ||
---|---|---|---|---|
Summer | Green | |||
Autumn | Green Orange Red | |||
Winter |
Position
- Full sun
- Partial shade
Aspect
South–facing or West–facing
Exposure
Sheltered Hardiness
H5Botanical 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
- Mollis azaleas are deciduous shrubs with unscented, funnel-shaped flowers in a range of colours from white through yellow and orange, to red, opening before the leaves in late spring
- Plant range
- Japan
How to grow
Cultivation
Grow in moist but well-drained, humus rich, acidic soil, in sun or light shade. Choose a site away from frost pockets and sheltered from strong winds. Mulch annually, ideally with leaf mould. See rhododendron cultivation for more detailed advice
Propagation
Propagate by seed or by semi-ripe cuttings in late summer
Suggested planting locations and garden types
- Cottage and informal garden
- Low Maintenance
- Flower borders and beds
Pruning
Prune lightly after flowering, see pruning group 1
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 powdery mildews, honey fungus, silver leaf and Phytophthora, as well as more specific Rhododendron diseases
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