• 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

Oenothera biennis

common evening primrose

  • Other common names common evening primrose
    coffee plant

    cure-all
    fever plant
    field primrose
    four o'clock
    German rampion
    large rampion
    night willowherb
    scabbish
    scurvish
    wild four o'clock

    see more
  • Synonyms Oenothera glabra Miller
    Oenothera odorata Hook. & Arn.

  • Family Onagraceae

  • Genus Oenothera can be annuals, biennials or perennials, upright or spreading in habit, with simple or lobed leaves and bowl-shaped, white, yellow or pink flowers over a long period in summer

  • Details O. biennis is an erect biennial to 1.5m, with a basal rosette of oblong leaves and long, leafy racemes of bowl-shaped, fragrant, yellow flowers which open in the evening in summer and autumn

Characteristics

  • Foliage Deciduous

  • Habit Columnar/Upright

  • 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)

    H7

Colour

Sunlight

  • Full Sun

  • Partial Shade

  • Aspect South-facing or West-facing

  • Exposure Sheltered

Soil

  • Loam

    Loam

  • Sand

    Sand

  • MoistureWell-drained

  • SoilLoam, Sand

  • pHNeutral, Acid, Alkaline

Size

  • Ultimate height 1-1.5 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 1-2 years

How to grow

Cultivation Grow in poor to moderately fertile, well-drained soil in full sun

Propagation Propagate by seed sown in early summer

Suggested planting locations and garden types Flower borders and beds Cottage & Informal Garden Wildflower meadow

How to care

Pruning Cut back after flowering

Pests Generally pest free

Diseases May be subject to powdery mildews and a leaf spot

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