• 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

Hemerocallis lilioasphodelus

yellow day lily

  • Other common names yellow day lily

  • Synonyms Hemerocallis flava
    Hemerocallis 'Lilioasphodelus'

  • Family Hemerocallidaceae

  • Genus Hemerocallis may be evergreen or herbaceous perennials, with narrow, strap-shaped leaves and funnel-shaped flowers on erect stems in late spring or early summer

  • Details H. lilioasphodelus is a spreading rhizomatous perennial to 80cm in height, with narrow leaves and fragrant, lily-shaped light yellow flowers 8-9cm in width

  • Plant range Europe Asia


  • Foliage Semi-evergreen

  • Habit Spreading / Branched

  • 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)




  • Full Sun

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

  • Exposure Exposed or Sheltered


  • Chalk


  • Chalk


  • Chalk


  • MoistureMoist but well-drained, Poorly-drained

  • SoilClay, Loam, Chalk

  • pHAcid, Alkaline, Neutral


  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.5-1 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in a fertile, moist but well-drained soil preferably in full sun. Copes well with heavy clay. May need watering in spring to early summer in dry conditions to ensure flowering

Propagation Propagate by division in spring or autumn; evergreen plants are best divided in spring

Suggested planting locations and garden types Flower borders and beds Low Maintenance Cottage & Informal Garden Prairie Planting Coastal

How to care

Pruning Remove spent flowers and remove dead foliage as required.

Pests Can get aphids and hemerocallis gall midge

Diseases May be affected by a leaf spot

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