• 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

Hypericum 'Rowallane'

St John's wort 'Rowallane'

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
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  • Other common names St John's wort 'Rowallane'

  • Synonyms Hypericum leschenaultii misapplied
    Hypericum 'Rowallane Hybrid'

  • Family Hypericaceae

  • Genus Hypericum can be annuals, perennials, shrubs or trees, evergreen or deciduous, with usually paired leaves and showy yellow flowers with prominent stamens, followed by capsules, occasionally berry-like

  • Details 'Rowallane' is an upright medium-sized semi-evergreen shrub with arching branches bearing ovate leaves and large, bowl-shaped, deep golden-yellow flowers to 7cm in width

Characteristics

  • Foliage Semi-evergreen

  • 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)

    H4

Colour

Sunlight

  • Full Sun

  • Partial Shade

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

  • Exposure Sheltered or Exposed

Soil

  • Chalk

    Chalk

  • Clay

    Clay

  • Sand

    Sand

  • Loam

    Loam

  • MoistureWell-drained, Moist but well-drained

  • SoilChalk, Clay, Sand, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 1.5-2.5 metres

  • Ultimate spread 0.5-1 metres

  • Time to ultimate height 5-10 years

How to grow

Cultivation Grows well in moist but well-drained soil in sun or partial shade

Propagation Propagate by semi-hardwood cuttings

Suggested planting locations and garden types Flower borders and beds Ground Cover Low Maintenance Banks and Slopes Cottage & Informal Garden

How to care

Pruning Pruning group 8

Pests Generally pest free

Diseases Generally disease free

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