Pruning is a fear for many novice gardeners - when to do it, how much to trim off and the risk of either losing this season's flowers or losing the plant completely.

Many use their secateurs cautiously, snipping off bits here and there, but you must remember that shrubs and trees will produce more flowers, fruit and vigour if you do the job properly.

And most deciduous shrubs can be left for a couple of years until they reach their full size, apart from removing weak, damaged or diseased branches.

So, which plants do you need to prune in spring?

Most faster-growing deciduous trees and shrubs which flower from early summer should be pruned in early spring, before growth starts.

These include buddleia, potentilla and fuchsia. Other plants which should be pruned now include hydrangeas, mid-summer and later-flowering (hybrid, large-flowered) clematis, climbing roses and modern rose bushes. Shrubs such as buddleia, lavatera and potentilla can be pruned hard, before growth starts.

Cut back old wood hard to a low bud, to encourage new growth which will bear flowers in the same year. Treat shrubs grown for their coloured bark, such as dogwood (Cornus alba) in the same way, to promote fresh young shoots with the brightest hues.

Large-flowered hybrid clematis bloom on new shoots and should be cut right back to a pair of fresh green buds about 30cm (1ft) above the ground in early spring.

It's a good idea to write specific pruning instructions on the label with the plant's name, for easy reference.

You can also using prunings from shrubs such as buddleia for plant stakes of all sizes, which look more natural than canes.

Don't prune anything now which flowers in spring and early summer, such as forsythia, kerria, weigela and philadelphus, or you will lose this year's flowers. The flowers are produced on shoots which developed during the previous growing season, so these flowering shoots should be cut back as soon as flowering has finished, to allow new shoots to form.

You should have left the flowerheads on hydrangeas over the cooler months to add winter interest and provide the plant with some protection, but now's the time to give them a late deadheading, snipping off the top of stems carrying the old flowers, taking them back to above the top healthy green bud. Don't prune them too hard or at other times of the year, or they won't flower.

Vigorous growers such as the climbing hydrangea (H. petiolaris) may have to be cut back with shears directly after flowering to keep them in check. Most evergreens, including conifers, only need a summer shape-up with shears if necessary (or in spring, if they are summer-flowering. Slow-growing shrubs such as hibiscus and azaleas need little pruning.

Of course, as with all shrubs, you may find the odd branch which sticks out, which you can shorten to tidy up the shrub at any time of the year.

If you inherit a garden with overgrown shrubs, cut out a third of the oldest stems in winter or spring, feed and mulch well, and continue the process for three years until all the old stems have been replaced.

They should be as good as new within a few seasons.