• 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 forrestii

Forrest St John's wort

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
  • Other common names Forrest St John's wort

  • Synonyms Hypericum patulum var. forrestii

  • 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 H. forrestii is a small, semi-evergreen shrub with ovate leaves which turn orange and red in winter. Flowers saucer-shaped, to 5cm in width, clear yellow

  • Plant range China to NE Myanmar

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)

    H5

Colour

Sunlight

  • Full Sun

  • Partial Shade

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

  • Exposure Sheltered or Exposed

Soil

  • Sand

    Sand

  • Clay

    Clay

  • Chalk

    Chalk

  • Loam

    Loam

  • MoistureWell-drained, Moist but well-drained

  • SoilSand, Clay, Chalk, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 1-1.5 metres

  • Ultimate spread 1-1.5 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 seed sown in containers in autumn or by semi-hardwood cuttings in summer

Suggested planting locations and garden types Banks and Slopes Flower borders and beds Hedging & Screens Low Maintenance City & Courtyard Gardens Coastal Cottage & Informal Garden

How to care

Pruning Pruning group 1 or pruning group 6

Pests Generally pest free

Diseases Generally disease free

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