• 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 laevigata

Japanese iris

Japanese iris

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  • Other common names Japanese iris
    smooth iris

  • Genus Iris may be rhizomatous or bulbous perennials, with narrowly 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

  • Family Iridaceae / Iridaceae

  • Details I. laevigata is a rhizomatous perennial to 70cm in height, with erect, sword-shaped leaves and rich purple flowers 8-10cm in width, each fall with a narrow white flash at the base

  • Plant range Temperate Asia

Characteristics

  • Foliage Deciduous

  • Habit Clump-forming

  • Toxicity Ingestion may cause severe discomfort

Colour

Sunlight

  • Full Sun

  • Aspect South-facing or West-facing

  • Exposure Sheltered or Exposed

Soil

  • Chalk

    Clay

  • Chalk

    Loam

  • MoisturePoorly-drained

  • SoilClay, Loam

  • pHAcid, Neutral

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 moist to wet, deep, humus-rich, acid soil; thrives at the margins of ponds or streams. Tolerates some lime

Propagation Propagate by division from mid-summer to early autumn

Suggested planting locations and garden types Flower borders and beds City & Courtyard Gardens Cottage & Informal Garden

How to care

Pruning No pruning required

Pests Sawflies may cause problems. Can be attacked by snails and slugs

Diseases Generally disease free

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