Weekend Work: Re-plant primrose and polyanthus

What to do

Various forms of primrose and polyanthus can be split and replanted as soon as they finish flowering. Set the new divisions in ground refreshed with bonemeal and compost. Each rosette of leaves can be prised away from the mother clump, with roots attached. Keep the newly planted pieces well watered until they are settled. Wilting plants may be victims of the dreaded vine weevil. Dig up affected plants and search through the roots for the fat white grubs. Then jump on them.

Early flowering shrubs such as forsythia can be pruned, taking out some of the old flowered branches at the base. Over-tall mahonias should also be reduced, by cutting down one or two of the tallest stems by half.

Grass is growing strongly again, but not strongly enough in our garden to gain ground from moss, which had a field day this wet winter. Fortunately, I like moss. If you don't, treat your lawn with a medicine that combines fertiliser with weed and moss killer.

Harden off bedding plants such as petunia and ageratum before planting them out when the weather warms up this month. I have not sown any flower seed outside yet, but with luck we can all catch up this month.

If you put on a thick layer of mulch now, you will be helping the soil to retain the moisture it has accumulated over the winter. A thick layer of organic matter on top of the soil also discourages annual weeds from germinating. Garden compost, mushroom compost (except around shrubs such as rhododendron which hate lime) or a ground bark mulch are all useful. So are untreated lawn mowings.

What to see

Twelve hopeful garden designers have made it through to the last, testing stage of Chris Beardshaw's Mentor programme, but only one can win a scholarship. All 12 will be building gardens at the Malvern Spring Gardening Show which runs from 7-10 May at the Malvern Showground, Worcestershire WR13 6NW and will also have to pitch to a 'Dragon's Den' of professionals at the show's Design for Living Theatre on 7 May. Entry for 7 May (£28) is by advance booking only, call 01684 584900. Tickets for 8 May (£16) and 9-10 May (£14) are available on the gate. For more information about the show, visit threecounties.co.uk/springgardening