A clump-forming herbaceous perennial with long stalks formed with divided green leaves and tall spikes packed with double, clear-blue flowers in summer. This plant was shortlisted for the Plant Heritage Threatened Plant of the Year 2025
1-1.5 metres
0.5-1 metres
| Season | Stem | Flower | Foliage | Fruit |
|---|---|---|---|---|
| Spring | ||||
| Summer | ||||
| Autumn | ||||
| Winter |
Will grow well in fertile, well-drained soil in full sun and apply a balanced liquid fertilizer every other week during the growing season. It will need shelter from strong winds; staking may be necessary. See staking perennials and delphinium cultivation for further advice
Propagate by basal cuttings in early spring
Deadhead spent flower spikes back to fresh flowering side shoots and cut back to ground level in late autumn
May be susceptible to aphids, earwigs, delphinium leaf miner, delphinium moth caterpillars, slugs, snails and caterpillars
May be susceptible to powdery mildews, delphinium black blotch, crown rot and viruses