Lift and divide congested clumps of spring-flowering perennials now they’ve finished flowering.
Early perennials like primulas (including candelabra, denticulata and polyanthus), pulmonaria, brunnera and dicentra are real treasures in the garden, providing a splash of colour soon after winter at the very start of the season, just when you need it most. These stalwart little garden performers arrive in the garden centre here in London from early autumn, so make a note in your diary to pop in and stock up to fill your borders with colour next spring.
All are quick growers and soon bulk up into sizeable clumps, but after about three or four years these can become congested and tired and stop flowering as enthusiastically.
The solution is straightforward: in early summer, preferably on a cool, cloudy day so your plants don’t dry out too quickly and become stressed, carefully dig up your clumps with a fork keeping as much of the root system intact as possible. Using your fingers, tease them gently apart, dividing the clump into several smaller plants.
Each plant should have a good tuft of leaves and plenty of healthy roots attached; snip out any spent flower heads or dead and discoloured foliage, and trim back any over-long roots to about 10cm. If the centre of the clump has become woody and old, discard it to keep just the young, vigorous plantlets to replant.
Boost the soil with some fresh compost and fork in a handful of slow-release fertiliser, then replant your healthiest division back in the same spot again. Water it in well and it will establish really quickly at this time of year, well in time to give you another spectacular display of flowers next year.
You can pot up the remaining divisions to give to family and friends, or replant them elsewhere in the garden.