• 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 'Viola' (LL)

clematis 'Viola'

  • Other common names clematis 'Viola'

  • 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

  • Horticultural Group Late Large-flowered clematis are deciduous climbers with large, star-shaped flowers to 15cm wide, opening on the current year's growth in summer and autumn

  • Details 'Viola' is a climber 2.5-3m high with green leaves and flowers, 8-15cm across, composed of five or six overlapping, wavy-edged, dark blue-violet sepals, and pale yellow anthers on green-white filaments, from midsummer to autumn; many clematis are visited by bees for pollen, and some also provide nectar


  • 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)




  • Partial Shade

  • Full Sun

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

  • Exposure Sheltered


  • Sand


  • Clay


  • Chalk


  • Loam


  • MoistureMoist but well-drained

  • SoilSand, Clay, Chalk, Loam

  • pHNeutral, Alkaline


  • Ultimate height 2.5-4 metres

  • Ultimate spread 1-1.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in full sun or partial shade in containers (at least 45cm deep and wide) or in the ground, in cool, moisture-retentive, well-drained soil, with the crown 5-8cm deep to encourage new shoots to grow from below ground level; keep the base of the plant and the roots cool and shaded by other plants or a layer of pebbles or flat stones; for more advice, see clematis cultivation

Propagation Propagate by internodal leaf-bud semi-ripe cuttings taken from spring to late summer, or by layering from late winter to spring

Suggested planting locations and garden types Wall-side Borders Flower borders and beds Hedging & Screens City & Courtyard Gardens Cottage & Informal Garden Patio & Container Plants

How to care

Pruning Pruning (clematis) group 3

Pests May be affected by aphids, capsid bug, caterpillars, and glasshouse red spider mite; flowers may be damaged by earwigs; young shoots are vulnerable to slugs and snails; container-grown plants may be affected by vine weevils

Diseases May be affected by clematis wilt, powdery mildews, fungal leaf spots, and virus diseases; pruned stems may be affected by clematis slime flux

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