Dahlia

Dahlias in Brighton

Dahlia pinnata

Show-stopping tuberous perennials that provide a spectacular display of colour from mid-summer right up until the first frosts. Ranging from enormous 'dinner plate' blooms to intricate pompoms and open-centred varieties that bees adore, they are a staple of the late summer UK garden.

Height100cm
SunlightFull Shade
WaterHigh Water

Growing Guide

Step-by-step instructions for growing Dahlia

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Growing Guide for

Change the guide to see different planting timelines and tips.

The most common UK method, starting tubers indoors in spring and planting out after frosts for summer blooms.

1
Start Tubers Indoors

1 Jan - 15 Jan

Place tubers in trays with moist compost, eye-side up, and cover lightly. Keep at in a bright spot indoors from 1st January - 15th January. Water sparingly until shoots appear.

2
Pot On Shoots

29 Jan - 5 Feb

Once shoots are tall, pot each tuber into individual containers with multi-purpose compost from 29th January - 5th February. Grow on in a bright, frost-free place.

3
Harden Off Plants

19 Feb - 26 Feb

Gradually acclimatise plants to outdoor conditions over 10-14 days from 19th February - 26th February. Place outside during the day and bring in at night, avoiding frost.

4
Plant Outdoors

26 Feb - 12 Mar

Transplant into well-drained, fertile soil in full sun after frosts from 26th February - 12th March. Space plants apart and water in well. Use fleece if cold nights are forecast.

5
Support and Pinch

12 Mar - 19 Mar

Insert stakes at planting to support tall stems. Pinch out the growing tip when plants reach to encourage bushiness from 12th March - 19th March.

6
Feed and Water

21 Nov - 19 Mar
every 2 weeks

Water regularly to keep soil moist, especially in dry spells. Feed every 14 days with a high-potash fertiliser from 21st November to boost flowering. Stop feeding by 19th March.

7
Deadhead Regularly

28 Nov - 30 Apr

Remove spent flowers weekly from 28th November to encourage continuous blooms. Cut back to a leaf joint to promote new buds.

8
Lift and Store Tubers

12 Dec - 26 Dec

After the first frost blackens foliage, cut stems back and carefully lift tubers from 12th December - 26th December. Dry, label, and store in frost-free conditions in dry compost or sand over winter.

Companion Plants

Plants that grow well (or poorly) with Dahlia

Why Companion Planting Matters

Companion planting can help deter pests, improve pollination, enhance growth, and maximize garden space. Some plants release chemicals that repel pests or attract beneficial insects, while others can improve soil quality or provide shade for sensitive plants.

Suggested Varieties

Popular varieties of Dahlia to consider

Bishop of Llandaff

A classic variety with dark foliage and bright red flowers, ideal for borders and excellent for pollinators.

Café au Lait

Popular for weddings, with large, creamy-pink blooms that can reach up to 25cm across.

Happy Days

A compact bedding type, perfect for containers, with prolific flowering in mixed colours.