• 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

Hydrangea paniculata 'Grandiflora'

hardy white-flowered hydrangea

  • Other common names hardy white-flowered hydrangea
    large-flowered paniculate hydrangea

  • Synonyms Hydrangea 'Pee Gee'

  • Family Hydrangeaceae

  • Genus Hydrangea can be deciduous or evergreen shrubs, or self-clinging climbers, with flowers in clusters usually comprising both small fertile and more showy sterile flowers; often good autumn colour

  • Details 'Grandiflora' is a large deciduous shrub with ovate leaves and broad panicles of, mostly, showy cream sterile florets which become pink-tinged with age, flowering from late summer


  • Foliage Deciduous

  • Habit Bushy

  • Toxicity May cause mild stomach upset if ingested

  • 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

  • Partial Shade

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

  • Exposure Sheltered or Exposed


  • Chalk


  • Chalk


  • Chalk


  • MoistureWell-drained, Moist but well-drained

  • SoilLoam, Clay, Sand

  • pHAcid, Neutral


  • Ultimate height 2.5-4 metres

  • Ultimate spread 1.5-2.5 metres

  • Time to ultimate height 5-10 years

How to grow

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

Propagation Propagate by softwood cuttings

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

How to care

Pruning Pruning group 1

Pests Can get aphids, capsid bug, glasshouse red spider mite and hydrangea scale

Diseases Generally disease free

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