Delphinium 'Secret'PBR
delphinium 'Secret'
A deciduous, herbaceous perennial that reaches to 130cm in height when in flower. It forms a mound of dark green, divided leaves and sturdy stems with rows of dark blue cupped flowers with dark centres, in summer
Size
Ultimate height
1–1.5 metresTime to ultimate height
1–2 yearsUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Moist but well–drained, Well–drainedpH
Alkaline, Neutral, AcidColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Blue Black | 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 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 fertile, well-drained soil in full sun. Shelter from strong winds and provide support (see staking: perennials). Divide every 2-5 years to maintain vigour. See staking: perennials and delphinium cultivation for further advice
Propagation
Propagate by division or by basal softwood cuttings in spring or Propagate by seed. As this plant is protected by Plant Breeders' Rights, any propagation should be for personal rather than commercial use
Suggested planting locations and garden types
- City and courtyard gardens
- Cottage and informal garden
- Wildlife gardens
- Cut flowers
- Flower borders and beds
- Wall side borders
Pruning
Deadhead spent flower spikes back to fresh flowering side shoots and cut back to ground level in late autumn.
Pests
May be susceptible to aphids, slugs, snails, leaf miners and caterpillars
Diseases
May be susceptible to powdery mildews, delphinium black blotch, crown rot and viruses
Get involved
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