Pruning should enhance the natural shape and performance of your shrub. But if you are happy with the size, shape and performance of a shrub, you don’t need to prune it! Simple as that!
♥ prune to remove dead or damaged wood or diseased branches
♥ improve shape or create special effects (hedge or topiary)
♥ rejuvenate old plants
♥ promote flowering (some shrubs like roses and butterfly bush produce more flowers if you prune them in spring)
♥ encourage reblooming (Bloomerang® Lilacs for example)
♥ prune to encourage fruit production, or colourful stems or foliage
♥ prune to keep a shrub smaller than it usually grows
When you select your flowering shrubs take in consideration how big the plant can grow (the ultimate size) and also where you want to place it! That will make your gardening much easier, you will have less care and less pruning!
Pruning can’t be done any time. Avoid pruning any flowering shrub in late summer or autumn because this can stimulate tender new growth and this can be damaged by cold temperatures.
Knowing if your plant flowers on new or old wood, helps you determine when it’s the best time to prune.
Spring flowering shrubs (early blooming plants such as Forsythia, purple Sandcherry, Flowering Almond, Llilac and Mockorange) bloom on “old wood” (on the previous season’s growth). In other words, the flowers actually developed on the plant late last summer. For maximum flower production next year, prune spring flowering shrubs immediately after they bloom.
Summer and early-autumn flowering shrubs (such as Butterfly Bush, Potentilas, Spireas, Rose of Sharon, Hydrangea paniculata) bloom on the current season’s growth or “new wood”. These plants should be pruned in late winter or just as growth starts in spring.
♥ Use clean, very sharp good-quality tools. Disinfect them immediately when finishing with one shrub (use alcohol or chlorine, diluted). This will prevent spreading possible diseases.
♥ Make your cuts as small as possible. The plants will heal up smaller cuts more quickly than a larger, slanted cut.
♥ Remove at first any dead and diseased wood. When removing old stems, cut them as close to the base of the stem.
♥ Cut back the suckers. These usually grow up vertical on the shrubs or trees and it’s very easy to detect them. Suckers usually do NOT make flowers and fruits!
♥ Also remove branches that are crossing or they are rubbing against each other.
♥ To keep good air circulation, keep the centre of the shrub open, removing long stems that are growing toward the middle of the plant.
♥ Always make the cut just ABOVE the bud! Not under and not on the bud.
♥ Do not leave stubs above the buds. They are a entry way for diseases and insects! Pruning cuts must have a smooth surface to heal properly.
♥ Prune in the summer to discourage growth.Plants DO NOT die if you leave them unpruned but many have been killed or disfigured from a drastic pruning. If you are in doubt, don’t prune! Pruning tips you can find here and here for Clematis and Hydrangea.