• 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

Inula magnifica

giant inula

  • Other common names giant inula

  • Family Asteraceae

  • Genus Inula may be annuals, herbaceous perennials or sub-shrubs, moslty with large basal leaves and daisy-like yellow flower-heads, often with narrow ray-florets

  • Details I. magnifica is an upright perennial to 2m tall, with branching purplish stems bearing hairy ovate leaves to 25cm long, and several deep yellow flower heads to 15cm wide in early summer

  • Plant range Caucasus

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • 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 South-facing or West-facing

  • Exposure Sheltered

Soil

  • Loam

    Loam

  • MoistureMoist but well-drained, Poorly-drained

  • SoilLoam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 1.5-2.5 metres

  • Ultimate spread 0.5-1 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in a deep, fertile, moist but well-drained soil in full sun. Will also tolerate boggy conditions

Propagation Propagate by seed in spring, or as soon as ripe in autumn, and sow into containers in a cold frame. Propagate by division in spring or autumn

Suggested planting locations and garden types Flower borders and beds Cottage & Informal Garden Wildflower meadow Wildlife Gardens

How to care

Pruning Cut back old stems and foliage as the plant dies back for the winter

Pests Generally trouble free

Diseases Powdery mildews may be a problem in conditions that are too dry

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