How to divide iris rhizomes

Do it:

Jul, Aug

Takes just:

30 minutes

Irises can become congested over time, which tends to inhibit flowering. This can be remedied by lifting and dividing their rhizomes to give them a little more space. Wait until flowering is over before dividing the iris clump, discarding any old, woody rhizomes and replanting only young, healthy plants into freshly-prepared soil.

You will need

  • Irises
  • Garden fork
  • Sharp knife
  • Trowel

Advertisement

Use a fork to dig up a congested clump of irises. Ease the plants from the soil, taking care not to spike the rhizomes.

Pull the congested rhizomes apart by hand, or cut them with a knife. Choose healthy pieces with leaves and discard old, woody sections.

Newly-planted rhizomes are vulnerable to wind rock, so it's a good idea to reduce the leaves by half. Use a sharp knife to trim them.

Replant healthy rhizomes about 12cm apart with the leaves facing towards the sun. Make a shallow hole and half bury the rhizome, giving it a firm push to bed it in - they like to bake in the sun, so don't bury them too deep.

Advertisement

It's a good idea to lift and divide clumps of irises every three years.

Discover more ideas and inspiration

Related content

How to divide bearded irises

How to divide congested bearded irises

How to divide primroses

Related offers

Offer

Buy one, get one free

Buy one hardy geranium 'Foundling's Friend' and get a beautiful geranium 'Rozanne' for free. Plant them this autumn and enjoy their long-lasting flowers next summer.

Order now

SAVE 20%

Save 20% at Crocus

Save 20 per cent across the entire range at Crocus, including everything from plants, trees and shrubs, to tools, furniture, outdoor living and more. Simply enter our discount code at checkout to claim this offer.

Use code: GWSEPT20

Order now

SAVE 20%

Save 20% on perennials

Save 20 per cent on all autumn-planting perennials at Sarah Raven. Choose from a vast range of plants, including geraniums, hellebores, wallflowers, delphiniums and much more.

Use code: GW17WAP

Order now