• 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

Salvia patens 'Cambridge Blue'

gentian sage 'Cambridge Blue'

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
gentian sage 'Cambridge Blue'

© RHS 1994

  • Other common names gentian sage 'Cambridge Blue'

  • Family Lamiaceae

  • Genus Salvia can be annuals, biennials, herbaceous or evergreen perennials, or shrubs. They have paired, simple or pinnately lobed, often aromatic leaves and 2-lipped flowers in whorls, forming simple or branched spikes or racemes

  • Details 'Cambridge Blue' is a tuberous-rooted herbaceous perennial to 75cm in height, with large, oval, pale green leaves and slender spikes of light blue, two-lipped flowers 2.5cm across

Characteristics

  • Foliage Deciduous

  • Habit Clump-forming

  • 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)

    H3

Colour

Sunlight

  • Full Sun

  • Aspect South-facing

  • Exposure Sheltered

Soil

  • Chalk

    Chalk

  • Clay

    Clay

  • Sand

    Sand

  • Loam

    Loam

  • MoistureMoist but well-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 2-5 years

How to grow

Cultivation Best grown in humus-rich, moist but well-drained soil in sun, shelter from cold winds

Propagation Propagate by seed

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

How to care

Pruning No pruning required

Pests May get slugs, snails and leafhoppers

Diseases Generally disease free

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