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How to grow Zinnia in the UK

Zinnia elegans

Zinnia growing in a UK garden

Zinnia (Zinnia elegans) is a flower that grows well in UK gardens. Hot-summer flower — plant in the sunniest spot. Direct sowing rarely works in UK. This guide covers when and how to sow Zinnia, 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 Zinnia

Sowing and harvest window through the year (UK):

Jan
Feb
Mar
Apr
Sow
May
Jun
Plant
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 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 Zinnia

No specific companion notes for this plant.

Grow Zinnia this year

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

Zinnia FAQs

When should I sow Zinnia in the UK?

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

How much sun does Zinnia need?

Zinnia prefers full sun (6+ hrs direct).

Is Zinnia easy to grow?

Easy — good for beginners. Hot-summer flower — plant in the sunniest spot. Direct sowing rarely works in UK.

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