Topiary is the art of training plants (typically evergreen shrubs and trees) into intricate or stylized shapes and forms.

The term may also be used more loosely to describe a number of garden features that rely on the close clipping and shaping of plants. These include:
 
Parterres: Typically lavish Italian renaissance gardens would have simple, large, clipped specimens in and among statues. These would then have beautifully ornate, clipped box hedges swirling around them in mirrored patterns or geometric designs. This style of hedging is known as a parterre garden. In earlier parterre gardens the gaps in the patterns would be left open and the ground would be covered with ornamental gravel to produce a crisp clean effect. As time went on, the styles became more and more elaborate, and other plants were added to give extra colour and interest.

Mazes and labyrinths: The Normans introduced pleasure gardens with mazes and labyrinths formed from clipped plants. A number of private and public gardens still have such features today.
 
Knot gardens: Topiary gardens became very popular in Great Britain during the reign of the Tudors and Stuarts. During this period knot gardens and clipped ornate shapes were introduced to gardens up and down the country. The knot garden was formed from different coloured box, planted in crisscrossing patterns so that it appeared that the ribbons of hedges had been tied up in knots. Highly-scented herbs were also used as hedging plants, planted in and among the gaps to give a tapestry of colour.   

Topiary is still used today in many modern styles, as there is always room for a clipped masterpiece.

Plants suitable for topiary

Traditional subjects for topiary have usually been evergreens to retain a permanent feature throughout the seasons.

Typically box (Buxus sempervirens) and yew (Taxus baccata) are used, however other evergreens such as privet (Ligustrum japonicum), holly (Ilex) and Lonicera nitida can be used.

Trees and shrubs can be bought ready-trained from specialist nurseries; these save time and effort, but can be expensive. Also available are plants with topiary frames over the top of them, which allow you to grow your own topiary with a little helping hand.

Choose a young, well-proportioned specimen with dense, healthy looking growth, especially near the base.

Recommended reading:

Topiary: the art of clipping trees and ornamental hedges by A.M Clevely (Collins 1988, 0004104226)

Topiary design and technique by Christopher Crowder & Michaeljon Ashworth (The Crowood Press 2006, ISBN 1861268165)

Topiary basics: the art of shaping plants in gardens & containers by Margherita Lombardi and Cristiana Serra Zanetti (Sterling Publishing 1999, ISBN 0806938994) – has great descriptions and information on the different plants that are suitable for topiary

These books are also made available through the RHS Lindley Library.

Trim annually with topiary shears or hedge-cutters in early or late summer to keep specimen in shape. Faster growing species may need to be trimmed twice or more each season. Suckers and unwanted branches can also be removed.

Starting your own topiary:

1. Decide upon the shape you wish to create. Balls, pyramids and cubes are a few of the easiest shapes to start with. Large or horizontal shapes may need more than one stem 
2. Choose which plant you would like, and whether it is to be grown in the ground or in a pot, and then plant it
3. To encourage strong, healthy growth, apply an annual dressing of Growmore and a mulch of organic matter in the spring
4. For standard specimens (e.g. lollipops), select one upright shoot to act as your main stem, tie this to a cane or stake and remove all others. Gradually clear the lower part of the stem of shoots and foliage, continuing until the desired height of main stem is reached (which could take several years)
5. Begin clipping it into shape. You could do this by eye or make a template or a wooden frame to ensure the shape is clipped uniformly
6. As the plant matures, it will bush out and the branches and leaves will become tightly knitted together to give the solid appearance. This can take many years, depending on the plant selected and the ultimate desired size
7. Allow for the plant to grow to the desired height before its main leader is trimmed

How to maintain existing topiary:

Existing specimens should be trimmed once or twice a year to maintain their shape; vigorous species may require more. Growmore can be applied once a year in the spring if desired, to help maintain the plant's vigour and appearance. Mulch with bark or organic matter if the plant is not surrounded by ornamental gravel.

Rejuvenation:

Once a topiary specimen has been neglected, all is not lost. The majority of evergreen plants will respond to hard pruning in early or mid-spring, especially yew, box and holly. Once it has been hard pruned, help promote new growth by feeding and mulching, and avoid drought stress in the following seasons. Depending on the species, it can take a few years for the specimen to grow back into its desired shape.

Containerized specimens:

Topiary can be grown in containers, but you need to make sure the pot is big enough for the specimen, and is well weighted to prevent it from falling over if the container has dried out or there are high winds.

Topiary frames:

Simple shapes such as balls can often be trained by eye. However, for more intricate shapes, frames are available. The subject for topiary specimens can range from fairies and mushrooms to horses and people. They are usually placed over the plant in the early stages of growth, allowing the plant to fill the frame to create the desired shape, acting as a former. Once the plant starts to protrude through the frame, prune once or twice a year through spring and summer to maintain the shape.

The frames can either be made out of galvanised wire or plastic-coated wire, which is usually green or grey. Some can be removed and reused, though most are just meant for one use and remain part of the structure of the plant, ultimately hidden from view by the foliage. The frames are often sold with a box plant ready to start.

Gardens to visit

Britain’s Finest online garden search
Levens Hall, Cumbria
 

• Download the RHS Garden Wisley app which features the Topiary and the Art of Clipping trail >

Establishment of any plant is essential for the plants survival and performance; however, large mature specimens often need more care and attention.

A large percentage of topiary piece are grown from box (Buxus sp.) so it is a good idea to be aware of box blight and box suckers. Be especially aware of box blight as if this is left undiscovered it can prove devastating to a garden full of box. The other disease to be aware of is Phytophthora root rot; yew specimens especially can be hard hit by this root disease.