This week I have been working with the students on the Royal Horticultural Society course tree planting, as the rain last weekend has made it an ideal time to plant out native tree whips. These trees have been grown from seed and grown on for two years to single stems with plenty of roots. Measuring 50cm long these trees should establish well. Now is a good time to plant trees and shrubs in the garden as most are still dormant and will move well. Container-grown plants as well will benefit from being planted at this time of year.

•The alpines and rock plants are not keen on the rain as they need to keep the tops dry to help prevent rots. It is worth repotting alpines now as they are starting to come into growth. Spend time on them picking off dead leaves and pulling out weeds that would otherwise spoil the show. A mulch of gravel chippings will make the rockery look good but even a handful around the base of choice plants will improve drainage. Alpines will establish readily at this time of year.

•It's time to sort out the gooseberries. Established bushes should have a main framework of six to eight main branches with these main shoots spaced well apart. Shorten these leaders by about a half to a bud facing in the right growing direction, usually facing outwards. Excess stems can be cut back to about 5cm. Cut out any shoots growing into the centre which could crowd the framework and affect light and air available to the fruits later on.

•Hortensis hydrangeas (Hydrangea x macrophylla) flower late in the season, but if you prune these too hard in spring you may suffer a lack of flowers that year. Cosmetic pruning from now to mid April is the order of the day. Remove dead flower heads, cutting the stems back to a strong pair of buds. By late summer these will have grown back and be producing new flowers.

•Don't put tender things outside yet as the weather is still very cold at night, and a late frost can kill tender specimens until late May.

•This week on the allotment I have been busy preparing for sowing early crops of broad beans, peas and all year round lettuce. I have been incorporating vast amounts of farmyard manure to help improve the soil. This is a job that should have been completed in winter but due to the rain and all those other excuses I have only just got round to it!

•Snowdrops are now starting to go over and this is the time to lift them and divide large clumps to spread them around the garden. Galanthus prefer dappled shade and they must not be allowed to dry out in summer. So incorporate some organic into the soil before planting and where possible apply a bark mulch. Always buy them 'in the green' (in leaf) as this is the most successful way of establishing them. Plant out in small clumps of four or five bulbs, ensuring they are planted at the same depth as before; settle them in with leaf mould or best garden compost.