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We have combined these two powerful search tools into a single Find a Plant service searching over 250,000 plant records.
Virtually all of the features of the old searches are still available and in addition we have added several new features to create a more comprehensive and user friendly search experience.
When using this search
Search by plant name, key attributes or both to find plant details and a list of
AGM plants have been through a rigorous trial and assessment programme. They are:
This plant will provide nectar and pollen for bees and the many other types of pollinating insects.
It is included in an evolving list of plants carefully researched and chosen by RHS experts. Divided into 3 groups these lists, linked below, are maintained by a team of RHS staff and are reviewed annually.
the RHS today and get 12 months for the price of 9
Other common names
swamp azalea swamp honeysuckle
white swamp honeysuckle
Rhododendron serrulatum Rhododendron oblongifolium
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
Viscosa azaleas are lax deciduous shrubs with fairly small leaves and trusses of funnel-shaped, fragrant flowers in early summer
R. viscosum is a bushy deciduous shrub to 2.5m tall, with dark leaves glaucous beneath. Very fragrant, narrowly funnel-shaped white flowers, up to 4cm wide, flushed deep pink on the tube, open in early to mid summer
Eastern N America
All ratings refer to the UK growing conditions unless otherwise stated. Minimum temperature ranges (in degrees C) are shown in brackets
Aspect South-facing or East-facing or West-facing
MoistureMoist but well-drained
SoilSand, Clay, Loam
Time to ultimate height
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
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
Flower borders and beds
City & Courtyard Gardens Cottage & Informal Garden
Pruning Pruning group 1
Pests May be attacked by vine weevil, rhododendron leafhopper, pieris lacebug, scale insects, caterpillars and aphids
May be affected by various Rhododendron diseases including powdery mildews, rhododendron petal blight, rhododendron bud blast, silver leaf and honey fungus
RHS members can get exclusive individual advice from the RHS Gardening Advice team.
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.