• 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

Iris 'Dusky Challenger' (TB)

iris 'Dusky Challenger'

  • Other common names iris 'Dusky Challenger'

  • Family Iridaceae

  • Genus Iris may be rhizomatous or bulbous perennials, with narrow leaves and erect stems bearing flowers with 3 large spreading or pendent fall petals, alternating with 3 erect, often smaller, standard petals, in late winter, spring or early summer

  • Horticultural Group Tall Bearded irises are herbaceous rhizomatous perennials to 70cm or more, with flowers 10-20cm across, bearded on the falls, in late spring and early summer

  • Details 'Dusky Challenger' is a clump-forming, rhizomatous perennial to 1m tall with narrow leaves. Well-branched stems bear chocolate-scented, dark purple, ruffled flowers in summer

Characteristics

  • Foliage Deciduous

  • Habit Clump-forming

  • Fragrance Flower

  • Toxicity Ingestion may cause severe discomfort

  • 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)

    H7

Colour

Sunlight

  • Full Sun

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

  • Exposure Sheltered

Soil

  • Loam

    Loam

  • Chalk

    Chalk

  • Sand

    Sand

  • MoistureWell-drained

  • SoilLoam, Chalk, Sand

  • pHNeutral, Alkaline, Acid

Size

  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in well-drained, fertile, neutral to slightly acid loam in full sun; sun on the rhizome encourages flowering. See also bearded iris cultivation

Propagation Propagate by division of rhizomes after flowering, from midsummer to late summer; for more advice, see dividing irises

Suggested planting locations and garden types Flower borders and beds Wall-side Borders Cut Flowers Drought Resistant Cottage & Informal Garden City & Courtyard Gardens

How to care

Pruning Cut down old flower stems after flowering, and remove any dying foliage in autumn

Pests May be affected by iris sawfly, aphids, leaf miners, slugs, snails, and wireworms

Diseases May be affected by iris rhizome rot, iris leaf spot, scorch, a rust, and virus diseases; for more advice see iris diseases

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