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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:
© RHS 1999
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Other common names
Thalictrum aquilegiifolium PURPLE CLOUD Thalictrum aquilegiifolium 'Purple Cloud'
Thalictrum delavayi 'Thundercloud'
Thalictrum can be rhizomatous or tuberous perennials with ternately or pinnately divided, often attractive foliage, and panicles or racemes of small flowers with showy stamens and sometimes large colourful petal-like sepals
'Thundercloud' is an erect herbaceous perennial to 90cm in height, with mid-green leaves composed of small, obovate leaflets, and branched stems bearing large fluffy heads of small flowers with prominent deep rose-purple stamens in early summer
Toxicity Contact with foliage may irritate the skin
All ratings refer to the UK growing conditions unless otherwise stated. Minimum temperature ranges (in degrees C) are shown in brackets
MoistureMoist but well-drained, Poorly-drained
SoilChalk, Loam, Clay
pHAcid, Alkaline, Neutral
Time to ultimate height
Grow in moist, humus-rich soil in partial shade
Propagate by seed in pots in a cold frame as soon as seed is ripe or in early spring. Propagate by division in spring as new growth begins
Suggested planting locations and garden types
Flower borders and beds Low Maintenance Underplanting of Roses and Shrubs
City & Courtyard Gardens Cottage & Informal Garden Prairie Planting Wildflower meadow
Pruning Cut down stems once flowering is over
Pests Slugs may be a problem
May be subject to powdery mildews in dry conditions
RHS members can get exclusive individual advice from the RHS Gardening Advice team.
We're a UK charity established to share the best in gardening. We want to enrich everyone's life through plants, and make the UK a greener and more beautiful place.
Join the RHS today and get 12 months for the price of 9