• AGM plants

    AGM plants have been through a rigourous trial and assessment programme. They are:

    • Excellent for ordinary use in appropriate conditions
    • Available to buy
    • Of good constitution
    • Essentially stable in form & colour
    • Reasonably resistant to pests & diseases

Thalictrum aquilegiifolium 'Thundercloud'

Rue 'Thundercloud'

AGM plants

AGM plants have been through a rigourous trial and assessment programme. They are:

  • Excellent for ordinary use in appropriate conditions
  • Available to buy
  • Of good constitution
  • Essentially stable in form & colour
  • Reasonably resistant to pests & diseases
Rue 'Thundercloud'

© � RHS 1999

  • Other common names Rue 'Thundercloud'

  • Synonyms Thalictrum aquilegiifolium PURPLE CLOUD
    Thalictrum aquilegiifolium 'Purple Cloud'

    Thalictrum delavayi 'Thundercloud'

    see more
  • Genus 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

  • Family Ranunculaceae / Ranunculaceae

  • Species '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

Characteristics

  • Foliage Deciduous

  • Habit Clump-forming

  • Toxicity Contact with foliage may irritate the skin

  • Hardiness

    Hardiness ratings

    All ratings refer to the UK growing conditions unless otherwise stated. Minimum temperature ranges (in degrees C) are shown in brackets

    • H1a - Under glass all year (>15C)
    • H1b - Can be grown outside in the summer (10 - 15)
    • H1c - Can be grown outside in the summer (5 - 10)
    • H2 - Tolerant of low temperatures, but not surviving being frozen (1 to 5)
    • H3 - Hardy in coastal and relatively mild parts of the UK (-5 to 1)
    • H4 - Hardy through most of the UK (-10 to -5)
    • H5 - Hardy in most places throughout the UK even in severe winters (-15 to -10)
    • H6 - Hardy in all of UK and northern Europe (-20 to -15)
    • H7 - Hardy in the severest European continental climates (< -20)
    Old hardiness ratings

    While we update our systems with the new hardiness ratings you may still see old hardiness ratings in your search results. These are denoted as 'Old'.

    • H1 - Requires heated glass
    • H2 - Requires unheated glass
    • H3 - Hardy outside in some regions of the UK
    • H4 - Hardy throughout the UK
    • H1 + H3 - Requires heated glass but may be grown outside in summer

    For full details of the hardiness ratings see

    see more

    H5

Colour

Sunlight

  • Partial Shade

  • Aspect East-facing

  • Exposure Sheltered

Soil

  • Chalk

    Chalk

  • Chalk

    Loam

  • Chalk

    Clay

  • MoistureMoist but well-drained, Poorly-drained

  • SoilChalk, Loam, Clay

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height

    0.5-1 metres

  • Ultimate spread

    0.1-0.5 metres

  • Time to ultimate height

    2-5 years

How to grow

Cultivation Grow in moist, humus-rich soil in partial shade

Propagation 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

How to care

Pruning Cut down stems once flowering is over

Pests Slugs may be a problem

Diseases May be subject to powdery mildews in dry conditions

Advertise here