About
Delphinium grandiflorum, the large-flowered delphinium or Siberian larkspur, is a short-lived perennial or annual with foliage finely divided into narrow lobes. Single, spurred flowers in brilliant blue, purple or white are produced in open, branching sprays in early summer. A charming and free-flowering species for a sunny, well-drained border.
About the genus
Delphinium, the larkspurs and delphiniums, are annuals, biennials and perennials with palmately lobed basal leaves and tall spikes, racemes or panicles of showy, spurred flowers in shades of blue, purple, pink, white or yellow in early summer. Among the most dramatic of all border perennials.
Growing conditions
SunlightFull sun
Soil typeChalk, Clay, Loam, Sand
Soil pHAcid, Alkaline, Neutral
Soil moistureMoist but well-drained
AspectSouth-facing, West-facing, East-facing
ExposureSheltered
UK hardinessH7
Plant details
Plant typeHerbaceous Perennial, Annual Biennial
HabitBushy
FoliageDeciduous
Height0.1-0.5 metres
Spread0.1-0.5 metres
Time to full height1 year
Suggested usesCottage and informal garden
Native toE & N Asia
ToxicityHumans/Pets: Harmful if eaten. Wear gloves and other protective equipment when handling. For further information and contact numbers regarding pets, see the HTA guide to potentially harmful plants
Care notes
CultivationGrow in a fertile, well-drained soil in full sun. See staking perennials and delphinium cultivation for further advice
PruningDeadhead spent flower spikes. After flowering, cut down all growth to ground level
PropagationPropagate by taking pencil-thick basal cuttings in early spring or by division
Pest resistanceMay be susceptible to aphids, earwigs, delphinium leaf miner, delphinium moth caterpillars, slugs, snails and caterpillars
Disease resistanceMay be susceptible to powdery mildews, delphinium black blotch, crown rot and viruses