• AGM plants

    AGM plants have been through a rigourous 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 'Langdon's Royal Flush'

Delphinium 'Langdon's Royal Flush'

Delphinium 'Langdon's Royal Flush'

© � RHS

  • Other common names Delphinium 'Langdon's Royal Flush'

  • Synonyms Delphinium 'Royal Flush'

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

  • Family Ranunculaceae / Ranunculaceae

  • Species 'Langdon's Royal Flush' is an erect herbaceous perennial to 1.5m in height, with erect racemes of white-eyed, deep rosy-pink flowers


  • Foliage Deciduous

  • Habit Columnar_Upright#Columnar/Upright

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



  • Full Sun

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

  • Exposure Sheltered


  • Chalk


  • Chalk


  • Chalk


  • MoistureMoist but well-drained, Well-drained

  • SoilSand, Chalk, Loam

  • pHAcid, Alkaline, Neutral


  • Ultimate height

    1-1.5 metres

  • Ultimate spread

    0.5-1 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

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

How to care

Pruning Deadhead by cutting spent flower spikes back to small flowering side shoots. Cut down all growth to ground level after it has withered in autumn

Pests May be attacked by slugs, snails, leaf miners and caterpillars

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

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