• 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

Borago officinalis

borage

  • Other common names borage
    cool tankard

    talewort
    tailwort

    see more
  • Family Boraginaceae

  • Genus Borago can be annuals or perennials, with coarsely hairy stems and simple leaves, with branched cymes of blue flowers

  • Details B. officinalis is a large, branched annual with coarsely hairy, ovate leaves and branched cymes of starry, bright blue flowers 2cm across over a long period in summer

  • Plant range Europe

Characteristics

  • Foliage Deciduous

  • Habit Spreading / Branched

  • 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 South-facing or West-facing or East-facing

  • Exposure Sheltered or Exposed

Soil

  • Chalk

    Chalk

  • Clay

    Clay

  • Sand

    Sand

  • Loam

    Loam

  • MoistureWell-drained

  • SoilChalk, Clay, Sand, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 1-2 years

How to grow

Cultivation Easy to grow in any reasonably drained soil in sun or partial shade. Dislikes transplanting

Propagation Propagate by seed

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

How to care

Pruning Leave to self-seed after flowering

Pests Foliage may be damaged by slugs and leaf-mining flies

Diseases May be affected by powdery mildews

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