Delphinium 'Guardian Blue' (Guardian Series)
delphinium 'Guardian Blue'
An upright herbaceous perennial 1.2m high with divided green leaves and strong stems, especially suitable for cutting, of deep blue flowers with white centres in early summer; delphiniums may be visited by bumblebees, especially long-tongued bumblebees
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Size
Ultimate height
1–1.5 metresTime to ultimate height
2–5 yearsUltimate spread
0.5–1 metresGrowing conditions
Moisture
Moist but well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Blue White | Green | ||
| Autumn | Green | |||
| Winter |
Position
- Full sun
Aspect
South–facing or West–facing
Exposure
Sheltered Hardiness
H6Botanical details
- Family
- Ranunculaceae
- Native to the UK
- No
- Foliage
- Deciduous
- Habit
- Columnar upright
- Potentially harmful
- Harmful if eaten. Wear gloves and other protective equipment when 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 but moisture-retentive soil in full sun, in a position sheltered 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, cutting spent flower spikes back to flowering sideshoots, and cutting all growth 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, crown rot and viruses
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