• 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

Ferula communis

giant fennel

giant fennel

© Mike L. Grant 2001

  • Other common names giant fennel
    meeting seed

  • Synonyms Ferula communis 'Gigantea'

  • Family Apiaceae

  • Genus Ferula are striking, large tap-rooted herbaceous perennials with big, pinnately divided leaves and compound umbels of small white, yellow or purple flowers; may die after flowering

  • Details F. communis is a robust perennial with large leaves divided into many slender segments, and branched stems bearing many rounded umbels of small yellow flowers in early summer

  • Plant range Mediterranean

Characteristics

  • Foliage Deciduous

  • Habit Columnar/Upright

  • 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)

    H3

Colour

Sunlight

  • Full Sun

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

  • Exposure Sheltered

Soil

  • Sand

    Sand

  • Loam

    Loam

  • Chalk

    Chalk

  • MoistureWell-drained

  • SoilSand, Loam, Chalk

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 2.5-4 metres

  • Ultimate spread 0.5-1 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in fertile, well-drained soil in full sun; protect with a dry, bracken mulch in winter. May die after seeding.

Propagation Propagate by seed in pots in a cold frame as soon as seed is ripe. Prick out seedlings into deep pots to allow tap root to develop

Suggested planting locations and garden types Flower borders and beds Architectural Cottage & Informal Garden Wildlife Gardens Mediterranean Climate Plants

How to care

Pruning To enhance foliage, remove flowering stems as soon as they appear or after blooming if seed is not required

Pests Prone to aphids and slugs

Diseases Generally disease free

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