Delphinium grandiflorum 'Summer Nights' (Summer Series)
delphinium 'Summer Nights'
A low-growing, short-lived perennial growing to 30cm tall and wide. In summer, loose sprays of single, spurred, bright blue flowers are held above the low, bushy mounds of foliage
Size
Ultimate height
0.1–0.5 metresTime to ultimate height
1–2 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
- Bushy
- 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. See staking: perennials and delphinium cultivation for further advice
Propagation
Propagate by taking pencil-thick basal cuttings in early spring or by division
Suggested planting locations and garden types
- City and courtyard gardens
- Cottage and informal garden
- Patio and container plants
- Flower borders and beds
- Cut flowers
- Garden edging
Pruning
Deadhead spent flower spikes. After flowering, cut down all growth to ground level
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
Get involved
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