Size
Ultimate height
1–1.5 metresTime to ultimate height
2–5 yearsUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Moist but well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Blue | Green | ||
| Autumn | ||||
| Winter |
Position
- Full sun
Aspect
South–facing or East–facing or West–facing
Exposure
Sheltered Hardiness
H5Botanical details
- Family
- Ranunculaceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Columnar upright
- Potentially harmful
- Humans/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
- Genus
Delphinium can be annuals, biennials or perennials, with palmately lobed basal leaves and showy bowl-shaped flowers in spikes, racemes or panicles
- Name status
Accepted
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. See staking: perennials and delphinium cultivation for further advice
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
- Cottage and informal garden
- Flower borders and beds
- Cut flowers
- Wall side borders
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 susceptible to aphids, earwigs, delphinium leaf miner, delphinium moth caterpillars, slugs, snails and caterpillars
Diseases
May be susceptible to powdery mildews in dry conditions, delphinium black blotch, crown rot and a virus
Get involved
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