• 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

Crocus etruscus 'Zwanenburg'

crocus 'Zwanenburg'

  • Other common names crocus 'Zwanenburg'

  • Family Iridaceae

  • Genus Crocus are dwarf, deciduous perennials growing from a corm, with linear leaves usually with a silvery central stripe, and goblet-shaped, sometimes fragrant flowers in autumn or early spring

  • Details 'Zwanenburg' is a perennial corm with flowers appearing before the leaves. Flowers lilac-blue, the outsides washed silver or biscuit-brown with faint purple veining

Characteristics

  • Foliage Deciduous

  • Habit Tufted

  • 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

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

  • Exposure Sheltered or Exposed

Soil

  • Sand

    Sand

  • Loam

    Loam

  • Clay

    Clay

  • Chalk

    Chalk

  • MoistureWell-drained

  • SoilSand, Loam, Clay, Chalk

  • pHAlkaline, Neutral, Acid

Size

  • Ultimate height Up to 10 cm

  • Ultimate spread 0-0.1 metre

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in a gritty, poor to moderately fertile soil

Propagation Propagate by seed sown in containers in a cold frame when ripe or remove cormlets when dormant

Suggested planting locations and garden types Banks and Slopes Flower borders and beds Gravel Garden City & Courtyard Gardens Coastal Cottage & Informal Garden Patio & Container Plants Rock Garden

How to care

Pruning No pruning required

Pests Corms are vulnerable to mice, voles and squirrels

Diseases Corms in storage may be subject to rots and moulds

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