PG Plan Your Garden

How to grow Sunflower in the UK

Helianthus annuus

Sunflower growing in a UK garden

Sunflower (Helianthus annuus) is a flower that grows well in UK gardens. Children's classic. Plant a Russian Giant for show; multi-headed types last longer. This guide covers when and how to sow Sunflower, 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
Harvest

When to sow & grow Sunflower

Sowing and harvest window through the year (UK):

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

Soil, position & care

Soil
Any reasonable, moisture-retentive but free-draining soil
Soil pH
6.0–7.5
Position
Full sun, sheltered from wind
Sowing depth
2 cm
Spacing
30–60 cm apart
Sowing
Sow indoors Apr or direct May
Growing
Stake tall varieties; very hungry and thirsty
Harvest & upkeep
Leave seed heads for the birds in autumn
Watch for
Slugs on seedlings, birds

Companion planting for Sunflower

Grows well with:

Courgette Cucumber Butternut Squash

Keep apart from:

Potato
Grow Sunflower this year

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Sunflower FAQs

When should I sow Sunflower in the UK?

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

What grows well with Sunflower?

Sunflower grows well alongside Courgette, Cucumber, Butternut Squash. Good companions can deter pests, attract pollinators or make better use of space.

What should you not plant near Sunflower?

Keep Sunflower away from Potato, which can compete with it or share pests and diseases.

How much sun does Sunflower need?

Sunflower prefers full sun (6+ hrs direct).

Is Sunflower easy to grow?

Easy — good for beginners. Children's classic. Plant a Russian Giant for show; multi-headed types last longer.

More flowers to grow

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