• 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 'Perry's Blue' (Sib)

Siberian iris 'Perry's Blue'

  • Other common names Siberian iris 'Perry's Blue'

  • Synonyms Iris sibirica 'Perry's Blue'

  • 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

  • Details 'Perry's Blue' is a clump-forming perennial, to 85cm in height, with slender strap-like grey-green leaves and striking sky blue flowers with white markings borne in early summer

Characteristics

  • Foliage Deciduous

  • Habit Clump-forming

  • 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

  • Partial Shade

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

  • Exposure Exposed or Sheltered

Soil

  • Clay

    Clay

  • Loam

    Loam

  • Chalk

    Chalk

  • Sand

    Sand

  • MoistureMoist but well-drained

  • SoilClay, Loam, Chalk, Sand

  • pHNeutral, 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 This cultivar is perfect for planting by a sunny waterside in moist but well-drained (not waterlogged), neutral to slightly acidic soil. Looks stunning planted in bold clumps. Plant in soil that has been improved with well-rotted manure or garden compost and do not allow to dry out, particularly as the plant is getting established

Propagation Divide clumps in early spring or autumn. If planted in a container, it will need dividing and re-potting every couple of years in spring

Suggested planting locations and garden types Flower borders and beds Low Maintenance City & Courtyard Gardens Cottage & Informal Garden Patio & Container Plants Coastal

How to care

Pruning Deadhead after flowering. Cut back foliage in autumn

Pests Slugs and snails may be a problem

Diseases May be affected by aphid borne virus diseases

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