• 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 pseudacorus 'Roy Davidson'

yellow flag 'Roy Davidson'

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
yellow flag 'Roy Davidson'

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  • Other common names yellow flag 'Roy Davidson'

  • Synonyms Iris 'Roy Davidson'

  • 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 'Roy Davidson' is a clump-forming perennial to 1.1m, the stems with 10 flowers or more, light yellow with light brown veining, the falls with a crescent-shaped brown central flash

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 East-facing or West-facing

  • Exposure Exposed or Sheltered

Soil

  • Chalk

    Clay

  • Chalk

    Loam

  • MoistureMoist but well-drained, Poorly-drained

  • SoilClay, Loam

  • pHAcid

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; it thrives at the margins of large ponds or streams; vigorous so site with care

Propagation Propagate by division of rhizomes from midsummer to early autumn

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

How to care

Pruning Remove any dying foliage in autumn, old flower stems can be cut down after flowering

Pests May be attacked by slugs, snails and thrips

Diseases Generally disease free

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