Rhododendron viscosum f. rhodanthum (Vs)
rose-flowered swamp azalea
A bushy, deciduous shrub to 2.5m tall, with dark leaves blue-green beneath. Very fragrant, narrowly funnel-shaped, pale pink flowers up to 4cm wide open from dark pink buds in early to mid-summer
Size
Ultimate height
1.5–2.5 metresTime to ultimate height
10–20 yearsUltimate spread
1.5–2.5 metresGrowing conditions
Moisture
Moist but well–drainedpH
AcidColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Blue Green | |||
|---|---|---|---|---|
| Summer | Pink | Blue Green | ||
| Autumn | ||||
| Winter |
Position
- Full sun
- Partial shade
Aspect
West–facing or East–facing or South–facing
Exposure
Sheltered Hardiness
H6Botanical details
- Family
- Ericaceae
- Native to the UK
- No
- Foliage
- Deciduous
- Habit
- Bushy
- Potentially harmful
- Harmful if eaten. Wear gloves and other protective equipment when handling
- 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
- Viscosa azaleas are lax deciduous shrubs with fairly small leaves and trusses of funnel-shaped, fragrant flowers in early summer
- Plant range
- China
How to grow
Cultivation
Grow in moist but well-drained, leafy, humus-rich acid soil in part shade with shelter; sun tolerant if soil remains reliably moist; 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
- Cottage and informal garden
- City and courtyard gardens
- Flower borders and beds
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
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