• 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

Clematis viticella

purple clematis

  • Other common names purple clematis

  • Family Ranunculaceae

  • Genus 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

  • Details C. viticella is a deciduous climber with open bell-shaped flowers 4cm across, with four broad purple or violet-blue tepals and creamy-yellow anthers in summer and early autumn

  • Plant range S Europe, W Asia

Characteristics

  • Foliage Deciduous

  • Habit Climbing

  • 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 North-facing or West-facing or East-facing

  • Exposure Exposed or Sheltered

Soil

  • Sand

    Sand

  • Clay

    Clay

  • Chalk

    Chalk

  • Loam

    Loam

  • MoistureMoist but well-drained

  • SoilSand, Clay, Chalk, Loam

  • pHAlkaline, Neutral

Size

  • Ultimate height 2.5-4 metres

  • Ultimate spread 1-1.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Tolerant of a range of garden soils but best grown in 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 root ball 5- 8cm (2-3in) below the soil surface to encourage new shoots from below soil level

Propagation Root softwood cuttings in spring or semi-ripe cuttings in early summer. 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

How to care

Pruning Pruning (Clematis) Group 3

Pests Slugs and snails, and voles may damage young shoots and cut through young stems. Aphids may attack young growth

Diseases Powdery mildew may be a problem; clematis wilt is unlikely to affect species clematis but graft failure or slug damage may cause wilting

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