How to grow Delphinium in the UK
Delphinium
Delphinium (Delphinium) is a flower that grows well in UK gardens. Slug bait essential or you'll lose all the new spring shoots. Stake before they need it. This guide covers when and how to sow Delphinium, the soil and position it likes, watering and feeding, companion planting, and when to harvest.
When to sow & grow Delphinium
Sowing and harvest window through the year (UK):
Jan | Feb | Mar | Apr Plant | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
Soil, position & care
- Soil
- Fertile, moisture-retentive but free-draining soil
- Soil pH
- 6.0–7.5
- Position
- Full sun, sheltered, rich soil
- Sowing depth
- Plant at the same depth as the pot
- Spacing
- 45–60 cm apart
- Sowing
- Sow spring or plant in autumn
- Growing
- Stake early — tall spires snap in wind
- Harvest & upkeep
- Cut spent spikes for a second flush; slug protection vital in spring
- Watch for
- Slugs and snails (devastate young shoots), powdery mildew
Companion planting for Delphinium
No specific companion notes for this plant.
Add Delphinium to your free 12-month plan and get watering & sowing reminders — no sign-up needed.
Delphinium FAQs
How much sun does Delphinium need?
Delphinium prefers full sun (6+ hrs direct).
When should I plant Delphinium in the UK?
In the UK, plant Delphinium in April. Planting in this window gives the roots time to establish before the plant is asked to grow away.
Is Delphinium easy to grow?
Moderate. Slug bait essential or you'll lose all the new spring shoots. Stake before they need it.