PG Plan Your Garden

How to grow Cornflower in the UK

Centaurea cyanus

Cornflower growing in a UK garden

Cornflower (Centaurea cyanus) is a flower that grows well in UK gardens. Wildlife favourite. Black Ball is a moody dark variety; classic blue is cottage garden gold. This guide covers when and how to sow Cornflower, the soil and position it likes, watering and feeding, companion planting, and when to harvest.

Type
Flowers
Difficulty
Easy — good for beginners
Position
full sun (6+ hrs direct)
Sow
April, September
Harvest

When to sow & grow Cornflower

Sowing and harvest window through the year (UK):

Jan
Feb
Mar
Apr
Sow
May
Jun
Jul
Aug
Sep
Sow
Oct
Nov
Dec

Soil, position & care

Soil
Any reasonable, moisture-retentive but free-draining soil
Soil pH
6.0–7.5
Position
Full sun for most; some tolerate light shade
Sowing depth
Surface to 1 cm (check light requirement)
Spacing
15–30 cm apart
Sowing
Sow under cover late winter–spring, or direct after the last frost
Growing
Water regularly; pinch tips for bushier plants
Harvest & upkeep
Deadhead often to prolong flowering
Watch for
Slugs and snails on seedlings; aphids on soft growth

Companion planting for Cornflower

No specific companion notes for this plant.

Grow Cornflower this year

Add Cornflower to your free 12-month plan and get watering & sowing reminders — no sign-up needed.

Cornflower FAQs

When should I sow Cornflower in the UK?

In the UK, sow Cornflower in April, September. Sowing across these months gives the plant the right soil temperature and day length to establish well.

How much sun does Cornflower need?

Cornflower prefers full sun (6+ hrs direct).

Is Cornflower easy to grow?

Easy — good for beginners. Wildlife favourite. Black Ball is a moody dark variety; classic blue is cottage garden gold.

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