Dividing Hostas is an easy way to increase your plants and rejuvenate mature clumps. Early spring is the best time to divide Hostas, just as new shoots begin to emerge. Use a garden fork to loosen the soil around the entire clump before gently lifting it from the ground. Shake off any loose soil to expose the root system.
Preparing Hostas for Division
I prefer to wash the root ball before dividing Hostas. This makes it easier to see the eyes, or growing points, and removes any weed seeds or slug eggs that may be hidden among the roots.
For large clumps, around 60cm (24 inches) wide or more, the easiest method is to place two garden forks back-to-back in the centre of the plant and gently pull apart. Smaller clumps can be divided using a clean, sharp knife or old putty knife. Insert the blade between the eyes and cut down through the crown before carefully separating the division.
How to Divide Hostas Successfully
Always clean and sterilise your tools before dividing Hostas to reduce the risk of spreading disease. Once divided, soak the new sections briefly in water containing a weak fungicide solution. Dust any cut surfaces with Flower of Sulphur to help protect against rot and infection.
Plant the new divisions immediately and never allow the roots to dry out. If you are not ready to replant them in the garden, pot the divisions into containers until a suitable planting position becomes available.
Planting Hosta Divisions
Avoid using high-nitrogen fertilisers at this stage, as the priority is to encourage strong root development rather than excessive leaf growth. A slow-release organic fertiliser applied at a low rate is ideal.
Prepare the planting area thoroughly by digging over the soil and incorporating organic matter. The planting hole should be at least twice the width of the root system to allow the division plenty of room to establish and grow.
Once planted, water thoroughly and keep the soil consistently moist during the first growing season while the plant becomes established.
For further planting advice, please see our guide on How to Plant Hostas.