Delphinium Black Knight Group
delphinium Black Knight Group
Erect perennials to 1.75m tall with lobed green leaves and spikes of semi-double, deep blue-purple flowers with black eyes in summer
Synonyms
Delphinium 'Black Knight'Delphinium 'Black Knight' Pacific hybrids
see moreDelphinium 'Tall Black Knight'
Size
Ultimate height
1.5–2.5 metresTime to ultimate height
2–5 yearsUltimate spread
0.5–1 metresGrowing conditions
Moisture
Moist but well–drained, Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Blue Purple | Green | ||
| Autumn | Green | |||
| Winter |
Position
- Full sun
Aspect
South–facing or West–facing or East–facing
Exposure
Sheltered Hardiness
H5Botanical details
- Family
- Ranunculaceae
- Native to the UK
- No
- Foliage
- Deciduous
- Habit
- Columnar upright
- Potentially harmful
- Harmful if eaten. Wear gloves and wash hands after handling
- 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 provide stakes or other supports. See staking: perennials and delphinium cultivation for further advice
Propagation
Propagate by basal softwood cuttings in spring, or by division in early spring or early autumn
Suggested planting locations and garden types
- City and courtyard gardens
- Cottage and informal garden
- Cut flowers
- Flower borders and beds
Pruning
No pruning required except deadheading; cut stems down to ground level at the end of the growing season
Pests
May be susceptible to aphids, earwigs, delphinium leaf miner, delphinium moth caterpillars, slugs, snails and caterpillars
Diseases
May be susceptible to powdery mildews, delphinium black blotch, grey moulds, sclerotinia disease, and cucumber mosaic virus
Get involved
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