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How to grow Delphinium in the UK

Delphinium

Delphinium growing in a UK garden

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.

Type
Flowers
Difficulty
Moderate
Position
full sun (6+ hrs direct)
Sow
spring
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.

Grow Delphinium this year

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).

Is Delphinium easy to grow?

Moderate. Slug bait essential or you'll lose all the new spring shoots. Stake before they need it.

More flowers to grow

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