Clipping hedges & topiary

Article by: Chris Beardshaw
Publish date: 2nd December 2008

Sculpting nature is no better epitomised than in the ancient art of topiary. Over the ages this practice of training trees and shrubs into predetermined shapes has served as an ornamental luxury in archaic gardens and become a popular ingredient in contemporary design. Even when it has fallen foul of fashion, topiary has held such an enduring appeal that we have revived it time and again to bring contrast against a sea of chaotic planting and a beat to a garden that lacks rhythm.

Although history tells us that topiary hails from Persia, it was the Romans who truly embraced the practice. Consul Pliny, a first century naturalist, wrote that many wild atriums of the grand villas of Rome had become landscaped miscellanies of elaborate battle scenes, fleets of ships and hunting tableaux clipped from the greenery by Greek slaves.

This desire to control nature has been carried through history and is illustrated in the knot gardens of Elizabeth I where low cut, interlocking box hedging formed orderly compartments where culinary herbs were grown for their uses and pleasurable aroma. Such verdant formality was equally popular in the Baroque gardens of the 17th Century, 'Topiary's Golden Age', where classical geometric design saw off naturalistic curves and unruly growth. Topiary is strongly associated with this period and features heavily in the fashionable formal grid designs of the time.

As Westerners worked hastily to create grand representational sculptures for the next duke, in the East, gardeners were subtly clipping full-sized specimens into miniature versions, gently coaxing trees to grow to their natural shape, but on a much smaller scale. Originally a Chinese technique, 'penjing' was later adopted by the Japanese and is more commonly known as bonsai. This ancient art of dwarfing larger specimens is achieved through pot confinement and the skilled pruning of the roots and leaves. The practice of creating downsized landscapes wasn't introduced into the West until the 1870s, yet it dates back almost 2,000 years, making it one of the oldest styles of topiary. Then the privilege of noblemen, today topiary in all its forms has become a rewarding facet of gardening for all. By combining what is natural with that which is sculpted, in modern design topiary is used to punctuate gardens, create structural divisions and used as an abstract silhouette against a backdrop of natural growth. Although there are many large estate gardens featuring eccentric and often humorous representational tree sculptures such as those of Levens Hall in Cumbria, contemporary topiary lends itself to the geometric shapes of pyramids, spirals, columns and spheres. These are easy shapes for beginners to try and highly popular, even dotted through the quintessentially herbaceous cottage garden.

There are a number of trees and shrubs used for modern topiary - mostly evergreen, but also some deciduous - that share characteristics: suitability for clipping, predominantly small leaved and a dense, well-clothed canopy to make pruning easier. They also boast short internodes, the distance of stem between leaves, so very little needs removing before the shears reach another of the many shoots. Perhaps the most commonly used evergreen for the popular spherical-shaped topiary is Buxus sempervirens, also known as box ball, that can be featured among riotous grasses to unify a wild garden. Buxus can also be used as a natural boundary to flank lawns, herb gardens or as part of gravel parterres.

For higher and more formal screens, the deciduous Carpinus betulus (hornbeam) is an ideal specimen. Five or six of these planted in a row are easily pleached into a raised hedge with interlocking branches that may eventually graft together. Although deciduous, the hornbeam will briefly hold on to its leaves as they fade to brown over winter. Similarly, Fagus sylvatica (beech) will keep its glorious coppery hues during the cold spell and cast a wonderful warm glow over a bleak winter garden. This is extremely aesthetic when cloud pruned, a similar technique to that used by Japanese bonsai masters. Cloud-shaped canopies are most appreciated when dusted with a layer of frost, transforming a tree into a surreal and mystical interpretation of a mountainous landscape. Ilex crenata (Japanese box-leafed holly) is perhaps the monarch of all evergreens used for bonsai-style trimming. Very simple to care for, this shrub - often compared to the Buxus Box - has luscious shiny leaves that respond well to clipping. It is slow growing and so retains its shape for long periods before it needs pruning.

The yew, Taxus baccata is an evergreen that looks superb when clipped into conical shapes, balls and pyramids with its thick, dark green foliage perfectly suited to these casts. Ancient yews can be found in all manner of shapes across the country, most notably the rather cloud like, undulating hedge in the grounds of Montacute House in Somerset. This hedge began life as a flat divide between the Marquess and his servants until frost ate away at it in the harsh winter of 1947. In fact, frost is one of the chief elements that can truly damage topiary. In the case of Montacute House, it added character to an otherwise normal yew hedge.

However, general maintenance of topiary requires shoots not to be cut during frost. Regular pruning is required, but this is not as complex as it may sound; as a general rule, clip evergreens once a year in late spring after fresh shoots emerge. Deciduous specimens can be trimmed either in late spring as buds swell or in later summer after growth has stopped. The most important implement for topiary is a sharply hewn pair of shears. Wet foliage prior to clipping as this will lubricate the leaves and allow for a clean cut. All topiary hedging performs best when a balanced feeding regime is employed throughout the year. If you have an inspired shape in mind, but do not feel very artistic, many shaped topiary meshes can be bought and used as a guide for cutting. The best idea is to start small and build on your art as it grows.

Topiary in all shapes and forms adds a sense of sophistication to a garden and can be teamed up with almost any planting partner imaginable. The resultant visual impact topiary creates, with its smooth geometry and rich colouring, makes a statement wherever it is featured, uniting the naturalistic with the formal and fascinating onlookers for years.