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How to grow Alliums in the UK

Giant purple pom-pom flowers on tall stems - ornamental onions, and bees love them.

• DifficultyEasy peasy
• WhereBeds or Pots
• Sunfull sun
• Grows to90cm
• Spacing20cm
• Time to first pickabout 30 weeks
• Typebulb

When to sow, plant and harvest alliums

Dates are for central England. Sow about two weeks later in the north and Scotland, and up to two weeks earlier in the south and south west. Get the dates for your postcode.

Planting it

1. Dig a hole to a depth of 15cm
2. Set each one in with the pointy end (or the shoots) facing up
3. Space them 20cm apart each way
4. Cover with soil, press down gently and water well
5. Push in a label so you don't dig them up by mistake

Top tips for growing alliums

• Plant bulbs 15cm deep in autumn.
• The seed heads look great dried, so leave them on.

Soil and feeding

Poor soil - really!. Nasturtiums flower best in poor soil. Feed them and you get all leaves and no flowers.

Harvesting and eating alliums

Cut a few for a vase, or leave the seed heads standing.

Saving your own alliums seed

They come back every year.

1. Leave the leaves to die back naturally - they feed next year's flowers
2. Bulbs slowly multiply underground. Every few years, dig up crowded clumps after the leaves die and replant them spread out

Where to buy alliums plants

Thompson & Morgan · Suttons · Amazon

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Alliums questions

When do I plant out alliums?

Plant alliums out from early September to mid November.

When can I enjoy alliums?

Alliums is ready from mid May to late June. Cut a few for a vase, or leave the seed heads standing.

How long do alliums take to grow?

Roughly 30 weeks from sowing or planting until the first harvest.

Are alliums easy to grow?

Alliums are rated 'easy peasy' for beginners, and can be grown in the ground or a raised bed or in pots and containers.