• 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

Centranthus ruber 'Albus'

red valerian (white form)

  • Other common names red valerian (white form)

  • Synonyms Centranthus alba
    Valeriana 'Alba'

  • Family Caprifoliaceae

  • Genus Centranthus may be annuals or perennials, with usually simple, opposite leaves and terminal clusters of small, trumpet-shaped flowers

  • Details 'Albus' is an upright perennial, sometimes grown as a biennial, with greyish-green leaves and sprays of small white flowers in late spring and summer

Characteristics

  • Foliage Semi-evergreen

  • Habit Columnar/Upright

  • 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

  • Aspect South-facing or West-facing

  • Exposure Exposed

Soil

  • Chalk

    Sand

  • Chalk

    Loam

  • Chalk

    Chalk

  • MoistureWell-drained

  • SoilSand, Loam, Chalk

  • pHAlkaline, 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 Grow in a well-drained soil that is poor to moderately fertile, ideally a chalky or stony soil. Good drought resistance; thrives on walls and in coastal gardens. Needs full sun to flower well.

Propagation Propagate by seed sown in spring

Suggested planting locations and garden types Flower borders and beds Low Maintenance Wall-side Borders Drought Resistant Cottage & Informal Garden Coastal Wildlife Gardens

How to care

Pruning Cut down stems in autumn or if self-seeding is a problem then cut back hard in July after their first flowering

Pests Generally pest free

Diseases Generally disease free

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