• 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

Hosta 'Devon Green'

plantain lily 'Devon Green'

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
  • Other common names plantain lily 'Devon Green'

  • Family Asparagaceae

  • Genus Hosta are clump-forming herbaceous perennials with simple, ovate or lance-shaped leaves, often attractively coloured or variegated, and erect racemes of nodding, funnel or bell-shaped flowers in early summer

  • Details 'Devon Green' is an upright, clump-forming perennial 50cm high by 60cm across with shiny, dark green leaves about 15cm long. The small, tubular flowers are pale purple with darker stripes and appear in late summer and early autumn

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • 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

  • Partial Shade

  • Aspect North-facing or East-facing or West-facing

  • Exposure Sheltered

Soil

  • Clay

    Clay

  • Loam

    Loam

  • MoistureMoist but well-drained

  • SoilClay, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.1-0.5 metres

  • Ultimate spread 0.5-1 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in fertile, moist but well-drained soil in part shade with shelter from cold, dry winds. See hosta cultivation

Propagation Propagate by division in late summer or early spring

Suggested planting locations and garden types Flower borders and beds Garden Edging Underplanting of Roses and Shrubs City & Courtyard Gardens Cottage & Informal Garden

How to care

Pruning Remove spent foliage as required and clear up dead foliage when it dies back at the end of the growing season

Pests May be attacked by slugs and snails; plants in pots may be susceptible to vine weevil

Diseases May be subject to a virus

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