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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
clematis 'Ken Donson'
Clematis can be deciduous or evergreen shrubs or herbaceous perennials, mostly climbing by twining leaf-stalks, and often with showy flowers. Some have attractive fluffy seedheads in autumn
Early Large-flowered clematis have large star-shaped flowers in early summer, often with a second flowering in late summer
'Ken Donson' grows to 2.5-3m, and has large, deep blue flowers with contrasting white filaments and bright yellow anthers making up the gold stamens. Flowers may be produced any time between June and September and followed by prominent seedheads
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 North-facing or West-facing or East-facing
MoistureMoist but well-drained
SoilLoam, Clay, Sand
pHAcid, Alkaline, Neutral
Time to ultimate height
Plant in a moisture-retentive, well-drained soil, with the roots and base of the plant kept cool and shaded by other plants or a layer of pebbles at the base. Plant with the crown 5-8cm deep to encourage new shoots to grow from below ground level
Propagate by softwood cuttings in spring, semi-ripe cuttings in summer or propagate by layering in late winter or early spring
Suggested planting locations and garden types
Flower borders and beds Wall-side Borders
City & Courtyard Gardens Cottage & Informal Garden Patio & Container Plants
Pruning Clematis pruning: group two
Pests aphids and slugs may be troublesome
Clematis wilt is an occasional problem
RHS members can get exclusive individual advice from the RHS Gardening Advice team.
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