Delphinium grandiflorum 'Summer Blues' (Summer Series)
delphinium 'Summer Blues'
A low growing, clump-forming herbaceous perennial with shorter stalks formed with divided green leaves and spikes packed with sky-blue flowers in summer.
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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–drained, Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Blue | Green | ||
| Autumn | Green | |||
| Winter |
Position
- Full sun
Aspect
West–facing or South–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
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
Propagation
Propagate by basal cuttings in early spring
Suggested planting locations and garden types
- City and courtyard gardens
- Cottage and informal garden
- Cut flowers
- Flower borders and beds
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, 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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