• 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

Ipheion 'Alberto Castillo'

starflower 'Alberto Castillo'

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
starflower 'Alberto Castillo'

© RHS

  • Other common names starflower 'Alberto Castillo'

  • Family Alliaceae

  • Genus Ipheion are small bulbous perennials with onion-scented, narrowly strap-shaped leaves and sweet-scented star-shaped flowers in late winter and spring

  • Details 'Alberto Castillo' is a deciduous perennial to 20cm tall, with narrow light green leaves and white flowers 4cm wide, each petal with a faint green central stripe, flowering in late winter and spring

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • Fragrance Flower

  • 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)

    H5

Colour

Sunlight

  • Full Sun

  • Aspect South-facing or West-facing

  • Exposure Sheltered

Soil

  • Sand

    Sand

  • Loam

    Loam

  • MoistureWell-drained, Moist but well-drained

  • SoilSand, Loam

  • pHAcid, Alkaline, 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 Plant 8cm deep in autumn in moderately fertile, humus-rich, well-drained soil that does not dry out. Provide protective winter mulch in colder areas. In containers best grown in loam based compost such as John Innes No. 2 with added leafmould and grit. Under glass grow in bright filtered light

Propagation Propagate by seed, sown in pots in a cold frame when ripe (cultivars may not come true from seed) or by division in summer when dormant

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

How to care

Pruning No pruning required

Pests Susceptible to damage by slugs and snails

Diseases Generally disease free

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