Growing guide

How to grow alliums

These ornamental onions are bold and architectural, with large rounded heads of usually purple flowers, followed by attractive seedheads. Weave them through sunny borders or combine them with feathery grasses for best effect.

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Quick facts

  • Easy to grow 
  • Flowers in spring and early summer
  • Best planted in well-drained soil 
  • Thrive in full sun and drought tolerant
  • Avoid damp sites on heavy soil
  • Propagate from offsets, aerial bulbils or seed
  • Good cut flowers
  • Attractive to pollinators

All you need to know

Before you get started
Ongoing care
While we think all this information will be helpful to you, we always recommend to read the instruction labels on your plants.

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