How to divide clump-forming perennials

How to divide clump-forming perennials

Find out how to divide clump-forming perennials in our practical, how-to guide.

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

Do not To do in January

Do not To do in February

Do To do in March

Do To do in April

Do To do in May

Do not To do in June

Do not To do in July

Do not To do in August

Do To do in September

Do To do in October

Do To do in November

Do not To do in December

Herbaceous perennials and bulbs can be divided to increase vigour to the original plant, or create new plants for free. There are several ways to divide plants – but the easiest to divide are those that naturally form clumps. Examples include heleniums, which grow separate rosettes, each with its own rootball, while Ranunculus aconitifolius readily produces new offsets.

Plants with separate rosettes and fibrous roots, such as primroses, can be dug up and divided as their flowers start to fade, while hostas and other perennials with impenetrable root balls can be cut up with a sharp knife or spade. Don’t forget spring bulbs, which can be lifted and prised apart as the foliage dies down.

Other plants to divide in spring include asters, astilbe, astrantias, Geranium himalayense and Sanguisorba menziesii.


You Will Need

  • Garden fork
  • Trug, or bucket
  • Congested perennial plants

Total time:

Step 1

Herbaceous perennial with rootball exposed
Herbaceous perennial with rootball exposed

Divide perennial plants when they’re dormant. Dig up the whole clump using a garden fork and shake off any surplus soil.

Step 2

Dividing the rootball of a plant
Dividing the rootball of a plant

Wash soil from the clump to reveal the roots and embryonic shoots. To get the maximum number of plants from your clump, separate out each chunk making sure it has one new shoot at the top.

Step 3

Individual clumps of root
Individual clumps of root

Pot chunks individually or plant them out in rows on spare ground. Keep the plants watered and fed, growing them on to a larger size before planting out into their final positions in autumn.