Divide overgrown perennials to renew your borders

Use this guide if your border plants have become crowded, flower less, or have dead centres with growth only round the edge. You need a garden spade, two garden forks, an old bread knife or sharp spade for tough roots, a bucket of water, compost, and labels.

Step by step

1. Identify which plants need dividing

   Look for clumps with a bare or woody centre, plants that flowered poorly this year, or ones spreading into their neighbours. Common candidates include hardy geraniums, asters, day lilies, hostas, phlox and many ornamental grasses. Plants such as peonies, hellebores and some deep-rooted perennials dislike disturbance, so leave them unless necessary. Make a list of the plants you plan to divide and where the pieces will go.