PG Plan Your Garden

How to grow Dahlia in the UK

Dahlia

Dahlia growing in a UK garden

Dahlia (Dahlia) is a flower that grows well in UK gardens. Cut for the vase obsessively — they flower more the more you pick. Cafe au Lait is the cult favourite. This guide covers when and how to sow Dahlia, 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 Dahlia

Sowing and harvest window through the year (UK):

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

Soil, position & care

Soil
Rich, free-draining soil
Soil pH
6.0–7.5
Position
Full sun, sheltered
Sowing depth
10–15 cm deep (varies by type)
Spacing
45–60 cm apart
Sowing
Start tubers under cover Apr; plant out after frost
Growing
Stake at planting; feed and water well; pinch out tips
Harvest & upkeep
Deadhead constantly; lift and store tubers frost-free over winter in cold areas
Watch for
Slugs and earwigs love them

Companion planting for Dahlia

No specific companion notes for this plant.

Grow Dahlia this year

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

Dahlia FAQs

How much sun does Dahlia need?

Dahlia prefers full sun (6+ hrs direct).

Is Dahlia easy to grow?

Moderate. Cut for the vase obsessively — they flower more the more you pick. Cafe au Lait is the cult favourite.

More flowers to grow

Pot Marigold Sunflower Sweet Pea Cosmos Nasturtium Nigella Cornflower Iceland Poppy