• 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

Lysimachia punctata 'Alexander' (v)

loosestrife 'Alexander'

loosestrife 'Alexander'

© RHS

  • Other common names loosestrife 'Alexander'

  • Family Primulaceae

  • Genus Lysimachia are herbaceous or evergreen perennials with simple leaves and star-shaped, cupped or bowl-shaped flowers in terminal racemes or panicles, or solitary in leaf axils

  • Details 'Alexander' is a vigorous perennial forming a substantial clump of erect stems with lance-shaped leaves boldly margined with cream and often tinged pink, and bowl-shaped bright yellow flowers 2.5cm wide in the upper leaf axils in mid summer

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)

    H6

Colour

Sunlight

  • Full Sun

  • Partial Shade

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

  • Exposure Sheltered or Exposed

Soil

  • Clay

    Clay

  • Loam

    Loam

  • MoistureMoist but well-drained

  • SoilClay, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Best grown in moisture retentive well-drained soil that does not dry out in summer, in full sun or part shade. Excessive vigour in moist soils can make it a determined spreader

Propagation Vigorous clumps can be divided in spring or autumn

Suggested planting locations and garden types Flower borders and beds City & Courtyard Gardens Coastal Cottage & Informal Garden

How to care

Pruning Remove faded flower stems to tidy

Pests May be damaged by slugs and snails

Diseases Generally trouble free

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