• 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

Agapanthus inapertus subsp. hollandii 'Sky'

African lily 'Sky'

African lily 'Sky'

© RHS

  • Other common names African lily 'Sky'

  • Synonyms Agapanthus inapertus 'Sky'
    Agapanthus 'Sky'

  • Family Agapanthaceae

  • Genus Agapanthus are clump-forming perennials with narrowly strap-shaped leaves, evergreen in some species, and erect stems bearing umbels of funnel-shaped blue or white flowers

  • Details

    'Sky' is a herbaceous perennial 1.5m high with deciduous strap-shaped green leaves and flowerheads of long, tubular, sky-blue flowers, darker near the tips, which hang down as they open in late summer

Characteristics

  • Foliage Deciduous

  • Habit Clump-forming

  • 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)

    H4

Colour

Sunlight

  • Full Sun

  • Aspect South-facing or West-facing or East-facing

  • Exposure Sheltered

Soil

  • Loam

    Loam

  • Chalk

    Chalk

  • Sand

    Sand

  • MoistureMoist but well-drained

  • SoilLoam, Chalk, Sand

  • pHNeutral, Alkaline, Acid

Size

  • Ultimate height 1-1.5 metres

  • Ultimate spread 0.5-1 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in moisture-retentive but well-drained soil in full sun, and in colder areas provide winter protection with a dry mulch; in containers, grow in loam-based compost such as John Innes No. 3, water freely when in growth but sparingly in winter, and apply a balanced liquid fertilizer monthly from spring until flowering; for more advice, see Agapanthus cultivation

Propagation Propagate by division between spring and early summer, or in early autumn after plants have finished flowering

Suggested planting locations and garden types Flower borders and beds Wall-side Borders Cut Flowers Low Maintenance Gravel Garden Prairie Planting Patio & Container Plants City & Courtyard Gardens Cottage & Informal Garden Mediterranean Climate Plants Coastal

How to care

Pruning No pruning required except cutting back dead flower stems, but allow them to remain until spring, because the seedheads look attractive over winter

Pests Generally pest-free but may be affected by slugs and snails and by agapanthus gall midge

Diseases Generally disease-free but may be affected by virus diseases

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