How to grow dahlias from seed

How to grow dahlias from seed

Follow the advice in this quick guide to sow and grow dahlias from seed.

A table displaying which months are best to sow, plant and harvest.
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Sow
Sow

Do not Sow in January

Do Sow in February

Do Sow in March

Do Sow in April

Do not Sow in May

Do not Sow in June

Do not Sow in July

Do not Sow in August

Do not Sow in September

Do not Sow in October

Do not Sow in November

Do not Sow in December

Plant
Plant

Do not Plant in January

Do not Plant in February

Do not Plant in March

Do not Plant in April

Do Plant in May

Do not Plant in June

Do not Plant in July

Do not Plant in August

Do not Plant in September

Do not Plant in October

Do not Plant in November

Do not Plant in December

Flowers
Flowers

Plant does not flower in January

Plant does not flower in February

Plant does not flower in March

Plant does not flower in April

Plant does not flower in May

Plant does not flower in June

Plant does not flower in July

Plant does flower in August

Plant does flower in September

Plant does flower in October

Plant does not flower in November

Plant does not flower in December

To do
To do

Do not To do in January

Do To do in February

Do To do in March

Do To do in April

Do not To do in May

Do not To do in June

Do not To do in July

Do not To do in August

Do not To do in September

Do not To do in October

Do not To do in November

Do not To do in December

Sown in late winter or early spring in a greenhouse or propagator, dahlia seeds will produce young plants ready to plant outdoors in late May to flower this year.

Seed companies sell a range of quick-growing bedding dahlias that are suitable for growing from seed. You can also use this method for sowing seeds saved from your own dahlia plants at the end of the previous season.

Related content:

Seed companies sell a range of quick-growing bedding dahlias that are suitable for growing from seed.

Follow these easy steps on how to sow dahlia seeds.

Advertisement

You Will Need

  • Seed tray or small pots
  • Multi-purpose, peat-free compost
  • Dahlia seeds
  • Clear polythene bags, Optional
  • Label and pencil

Step 1

Fill a pot or seed tray with moist compost and lightly firm the surface. Gently push your dahlia seeds into the compost. Don’t forget to label your seeds. Cover pots with an inflated clear polythene bag, held in place with a rubber band. If sown in seed trays, cover with a propagator lid.

Sowing dahlia seed
Sowing dahlia seed

Step 2

Seedlings will germinate within a couple of weeks. Once the ‘true’ leaves have grown, seedlings are ready to transplant into individual pots. Hold plants by their leaves and gently tease them out of the soil.

Transplanting dahlia seedlings
Transplanting dahlia seedlings

Step 3

Gently transplant seedlings in 10cm pots of peat-free, multi-purpose compost, firm and and water well. In mid-May, harden off plants by standing them outdoors during the day and bringing them in at night. Plant them in their final positions once all risk of frost has passed.

Young dahlia plants
Young dahlia plants
Advertisement

Allow a few dahlia flowers to set seed for collection at the end of September. Save them in an envelope over winter to sow in February. You’ll get a wonderful mixture of different flower shapes and colours from the resulting plants.

Red watering can