Beginners Guide to Shrub Pruning in Spring

Pruning is done to remove dead, diseased and damaged growth, to encourage new growth as well as flower and fruit bud formation. The size and shape of plants can be controlled by pruning. To gain a better understanding of the principles and techniques of pruning it is necessary to ask why a particular plant is being grown. Many shrubs can be pruned in more than one way to create different effects.

Pruning Shrubs Grown for Bright Stem Colour

Shrubs with bright stems in winter such as Cornus alba ‘Siberica’ and Salix alba vitellina ‘Britzensis‘ should be pruned in March/April. Cut back all shoots to within two buds of last year’s growth.. Left un-pruned these vigorous stalwarts of the winter garden become unruly, losing their intense stem colouring.

Pruning Shrubs Which Flower From Mid to Late Summer

Those shrubs which flower on current year’s growth, from mid to late summer include Buddleja davidii (butterfly bush) and Lavatera arborea (tree mallow). Pruned in spring they have enough time to produce flowering wood in the same season. Prune back all last year’s growth to within two buds of the base. Left alone they become leggy with bare stems at the bottom and flowers only near the top. A Buddleja growing towards the back of a large border can be pruned less severely if extra height is desired. Its bare bottom can be screened with foreground planting.

Pruning Vigorous Ground Covering Shrubs

Vigorous ground covers such as Hypericum calycinum (Rose of Sharon) and Vinca species (periwinkle) react brilliantly to a close shave. Remove all above-ground growth in spring with shears. A fresh crop of shiny healthy leaves will be the result.

When and How to Prune Clematis Species

Clematis which flower on this year’s growth respond to hard pruning. Cut back shoots to 15-30cm above ground level before growth starts in spring. Clematis ‘Jackmanii’, Clematis viticella and Clematis tangutica fall into this category. Clematis alpina and several other species flower during spring and early summer on last year’s ripened shoots. Cutting them back in spring would remove all the current year’s flowers.

Pruning to Produce Large foliage

Cotinus coggygria (smoke bush) responds to hard pruning at the end of March by producing large eye-catching foliage. If, however, the smoke like inflorescences for which this shrub is well known are to be enjoyed then don’t go near them with secateurs, except to remove unhealthy wood.

Know Your Plants and Keep Pruning Simple

It is vital to know the name of the plant to be pruned, because not all species in a particular genus are pruned in the same way. Knowing when a shrub or climbing plant flowers or has its main season of attraction is the key to keeping the task of pruning simple. If in any doubt about a particular plant, check out the recommended pruning method in a good reference book like The Royal Horticultural Society Pruning and Training Manual published by Dorling Kindersley.