• 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

Delphinium 'Centurion Sky Blue' (Centurion Series)

delphinium 'Centurion Sky 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
  • Other common names delphinium 'Centurion Sky Blue'

  • Synonyms Delphinium × cultorum 'Centurion Sky Blue'

  • Family Ranunculaceae

  • Genus Delphinium can be annuals, biennials or perennials, with palmately lobed basal leaves and showy bowl-shaped flowers in spikes, racemes or panicles

  • Details 'Centurion Sky Blue' is a perennial cultivar of striking light azure blue flowers with white central bees. Its sturdy stems reach 1.5m

Characteristics

  • Foliage Deciduous

  • Habit Columnar/Upright

  • Toxicity All parts may cause severe discomfort if ingested and may irritate skin

  • 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

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

  • Exposure Sheltered

Soil

  • Sand

    Sand

  • Chalk

    Chalk

  • Loam

    Loam

  • Clay

    Clay

  • MoistureMoist but well-drained

  • SoilSand, Chalk, Loam, Clay

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 1-1.5 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in a fertile, well-drained soil in full sun; shelter from strong winds and stake well. Apply a balanced liquid every couple of weeks in the growing season. For the best flower spikes thin shoots when 7cm high to leave a minimum of 2-3 shoots on young plants and 5-7 shoots on established plants

Propagation Propagate by taking pencil thick basal cuttings in early spring or propagate by seed in spring or autumn (cultivars will not come true)

Suggested planting locations and garden types Cut Flowers Flower borders and beds Wall-side Borders Cottage & Informal Garden

How to care

Pruning Deadhead spent flower spikes. After flowering, cut down all growth to ground level. If fed and watered well, a second flush of flowers will be produced in autumn

Pests May be attacked leaf miners and caterpillars. Young growth in early spring is especially vulnerable to slugs and snails

Diseases May be subject to powdery mildews if too dry, delphinium black blotch, crown rot and a virus

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