How to Prune safely and effectively

Whether they are grown in a pair of sleek galvanised steel containers outside your front door or planted among perennials in a border, box topiary shapes are among the most useful plants in the garden, providing structure, texture and all year round colour.

Although box balls, cones, cubes, pyramids, domes, spirals and a menagerie of animal shapes are among the trendiest things you can grow, they quickly lose their appeal when a crisp outline is lost beneath a shaggy coat of new growth. The answer: give plants a trim in June.

When to prune

Box will burst into life in March and lots of lime-coloured shoots will soon conceal the dark green shape beneath. Although you'll be itching to prune shoots back as soon as possible, don't.

Trimming young, sappy growth in the spring is likely to bruise the foliage, leaving you with a topiary shape that is unsightly. It is best to prune in mid-June, when the leaves are hard and leathery, and again in late summer if necessary. Don't worry if you did prune in the spring, the bruising will be eventually hidden by the subsequent flush of growth.

How to prune

It's possible to trim simple shapes - such as cones and balls - by eye, but for greater accuracy use a garden cane as a cutting guide for straight edges or make a template.

To prune balls, take a length of garden wire and twist it into a circular shape that can be held and moved over the plant as you prune. To ensure you are left with a perfect sphere, make the frame smaller than the mass of foliage.

Restore a cone shape by standing above the plant and pruning in an outward direction from the centre, working around the plant with an easy to handle set of secateurs. Alternatively, rest three canes on the sides of the cone and push into the ground. Secure the canes at the top to make a wigwam and bind the sides together with garden wire. Use your shears to prune to this framework.

Topiary spirals may look complicated, but it is easy to re-establish an overgrown specimen. Working from top to bottom with your secateurs, prune the upper surface of the spiral making sure you remove the foliage as far back as the main stem. Next, trim the upper and then the lower turn of the spiral to create its curved edges.

With practice, pruning topiary is a doddle. For the greatest success use a pair of hand held trimmers to leave a lovely clean finish, and regularly step back to double check your progress - unfortunately, if you make a mistake there's no turning back.

Pruning a Deciduous Shrub - Deciduous shrubs such as Forsythia (Yellow Bell's), are those that lose their foliage during the winter season and have a unique ability to renew themselves almost indefinitely. Some of these shrubs growing in the eastern part of the country are alive and healthy after more than a century, yet these plants don't appear to be to be more than five years old. The secret is proper pruning. Each year a deciduous shrub produces many shoots from the plants base or roots. Wait to begin pruning deciduous shrubs until they are three years old. The best time to prune deciduous shrubs that do not bloom in Spring is late winter. Wait to prune shrubs that flower in Spring until after they bloom. The goal is to remove all but 1/3 of the plants shoots. Below is a basic guidline for pruning deciduous shrubs.