• 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

Diplarrena moraea

butterfly flag

butterfly flag

© RHS

  • Other common names butterfly flag

  • Family Iridaceae

  • Genus Diplarrena are rhizomatous, evergreen perennials related to irises. They are clump-forming, producing tufts of stiff linear to sword-shaped leaves to 30cm, the flowers borne above the leaves on wiry stems. Flowers 2-3 in a terminal cluster, with 3 large, white outer segments, the inner 3 more erect and usually coloured

  • Details D. moraea has narrow leaves and wiry stems 45-60cm. Flowers are white, 4-6cm across, the inner segments purple and yellow, in summer. Fragrant

  • Plant range SE Australia

Characteristics

  • Foliage Evergreen

  • Habit Columnar/Upright

  • Fragrance Flower

  • Toxicity Causes severe discomfort when ingested

  • 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

  • Partial Shade

  • Aspect South-facing or West-facing

  • Exposure Sheltered

Soil

  • Sand

    Sand

  • Loam

    Loam

  • MoistureMoist but well-drained

  • SoilSand, Loam

  • pHAcid, Neutral

Size

  • Ultimate height 0.1-0.5 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in a sunny position in a humus-rich, moist neutral to acid soil. Partial shade is suitable when planted in a hot site

Propagation Propagate by seed sown in containers in a cold frame in autumn or spring. Can also be propagated by division in spring

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

How to care

Pruning None required

Pests Generally trouble free

Diseases Generally trouble free

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