Delphinium
Delphinium elatum hybrids
Delphiniums produce towering spikes of blue, purple, pink or white flowers in early summer and are the backbone of classic English borders. They need cool summers, rich soil and staking.
Photo: Björn S. · CC BY-SA 3.0, via Wikimedia Commons
Essential Care Requirements
Light
Full sun
Watering
Moderate
Water deeply in dry weather.
Soil
Rich, well-drained soil; pH 6.5–7.5.
Temperature and humidity
-35–27 °C · Moderate humidity
Feeding
Feed generously in spring with a balanced fertilizer.
Pruning and propagation
Propagate by division, stem cuttings, seed
Stake spikes early; cut back after flowering for a second flush.
All parts are highly toxic if eaten by people or animals.
Top Cultivation Tips
Protect young shoots from slugs.
Shelter from wind.
Grow larkspur instead in hot climates.
Thin shoots in spring for stronger spikes.
Common problems
Powdery mildew
A fungal disease that coats leaves, buds and young shoots with a white, flour-like dust, weakening the plant and spoiling flowers and fruit.
How to treat it →DiseaseRoot rot
Roots decay in waterlogged soil, so the plant wilts and yellows even though the soil is wet.
How to treat it →PestSnails and slugs
Night-feeding molluscs that chew ragged holes in leaves, seedlings and soft stems, especially in wet weather.
How to treat it →
