• 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

Nepeta 'Six Hills Giant'

catmint 'Six Hills Giant'

  • Other common names catmint 'Six Hills Giant'

  • Synonyms Nepeta × faassenii 'Six Hills Giant'
    Nepeta × gigantea

  • Family Lamiaceae

  • Genus Nepeta can be annuals or, more commonly, perennials, with paired, usually aromatic leaves, and terminal spikes or panicles of 2-lipped, tubular flowers

  • Details 'Six Hills Giant' is a vigorous perennial forming a clump of aromatic, grey-green leaves, with lavender-blue flowers in spikes in summer

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • Fragrance Foliage

  • 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)

    H7

Colour

Sunlight

  • Full Sun

  • Partial Shade

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

  • Exposure Exposed or Sheltered

Soil

  • Sand

    Sand

  • Clay

    Clay

  • Chalk

    Chalk

  • Loam

    Loam

  • MoistureWell-drained

  • SoilSand, Clay, Chalk, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.5-1 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in any well-drained soil in full sun or partial shade. May need support

Propagation Propagate by division in spring or autumn. Propagate by softwood cuttings in early summer

Suggested planting locations and garden types Underplanting of Roses and Shrubs Drought Resistant Flower borders and beds Wildlife Gardens Cottage & Informal Garden Gravel Garden

How to care

Pruning Trim after flowering to keep plants compact and to encourage a second flowering

Pests May be attacked by leafhoppers

Diseases May be subject to powdery mildews

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