• 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

Verbascum (Cotswold Group) 'Cotswold Beauty'

mullein 'Cotswold Beauty'

mullein 'Cotswold Beauty'

© RHS

  • Other common names mullein 'Cotswold Beauty'

  • Family Scrophulariaceae

  • Genus Verbascum can be annuals, biennials, perennials or subshrubs mostly with hairy leaves and 5-petalled, saucer-shaped flowers

  • Details 'Cotswold Beauty' is a short-lived semi-evergreen perennial to 1.2m tall, with a basal rosette of broadly ovate, dark green leaves and erect spikes of light buff flowers 3-4cm across, with purple stamens

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)

    H6

Colour

Sunlight

  • Full Sun

  • Aspect South-facing or West-facing

  • Exposure Exposed or Sheltered

Soil

  • Chalk

    Chalk

  • Sand

    Sand

  • Loam

    Loam

  • MoistureWell-drained

  • SoilChalk, Sand, Loam

  • pHAlkaline

Size

  • Ultimate height 1-1.5 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 1-2 years

How to grow

Cultivation Prefers a poor, well-drained alkaline soil in full sun. If grown in a more fertile soil the plants become larger and will need support

Propagation Divide mature plants in the spring or take root cuttings in winter

Suggested planting locations and garden types Flower borders and beds City & Courtyard Gardens Coastal Cottage & Informal Garden Gravel Garden

How to care

Pruning Cut back old stems to the base after flowering

Pests figwort weevil and some moth caterpillars can be a problem

Diseases Can be susceptible to powdery mildews

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