• AGM plants

    AGM plants have been through a rigorous 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

Paeonia × smouthii

© Dorling Kindersley Ltd
  • Synonyms Paeonia 'Smouthii'

  • Family Paeoniaceae

  • Genus Paeonia may be herbaceous perennials or deciduous sub-shrubs with large, divided leaves and showy large bowl-shaped flowers, usually in early summer

  • Details P. x smouthii is a clump-forming herbaceous perennial to around 70cm tall with foliage divided into dark green leaflets. Fragrant, single, dark crimson flowers to 10cm in diameter with conspicuous yellow stamens are borne in profusion in spring

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • Fragrance Flower

  • Toxicity All parts can cause stomach upset if eaten

  • 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)

    H6

Colour

Sunlight

  • Full Sun

  • Partial Shade

  • Aspect South-facing or West-facing or East-facing

  • Exposure Sheltered

Soil

  • Sand

    Sand

  • Loam

    Loam

  • Clay

    Clay

  • MoistureMoist but well-drained

  • SoilSand, Loam, Clay

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.5-1 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Best in a deep, fertile, humus-rich soil that is moist but well-drained in a sheltered position in full sun or partial shade. Long-lived but resents disturbance. See herbaceous peony cultivation

Propagation Propagate by division in autumn or early spring

Suggested planting locations and garden types Cut Flowers Flower borders and beds Cottage & Informal Garden

How to care

Pruning Remove dead flowers as they fade, then cut plant back as the foliage dies down in autumn

Pests Can be affected by leaf and bud eelworm and soil-dwelling swift moth caterpillar

Diseases May be subject to a virus, honey fungus and peony wilt

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