Topiary, knots and parterres come in many guises, from the grand and imposing to the humble and folksy. In this book Caroline Foley - with the aid of diarists, writers, wits, designers, gardeners and garden owners - traces their story through the centuries and across the world.

Starting from the topiary of patrician Rome, she moves through the paradise gardens of Islam and the medieval hortus conclusus to the formal parterres of Renaissance Italy, the more elaborate broderies of the royal French gardens, the complicated conceits of the Tudors and the geometry of the Dutch school. She takes a wry look at the eighteenth century, when many fine formal gardens were scrapped in favour of the English landscape movement (which, in fact, was no less artificial). In the nineteenth century there was a revival of parterres filled with tender bedding plants.

Green architecture returned with the Arts and Crafts movement, and the twentieth century saw a joyful resurgence of the topiary peacock and other such conceits, the arrival of the Japanese minimalist school, the cult of the venerable sagging hedge, cloud pruning and the emergence of the cool crisp lines of modernism. German perennial planting, juxtaposed with sharply cut linear hedges, has provided a clever solution to the modern requirements of high style, low maintenance and attention to the environment and to labour costs. Of late a new type of formality has emerged among designers and landscape architects, involving wild-looking prairie planting set off by large-scale sculptural topiary.

As Caroline Foley points out, 'Serious or frivolous . . . topiary always has character and presence. While wonderfully impressive when it takes the form of an immaculate battlemented bastion, it has poetry and possibly even greater charm when it is overblown and blowsy with age. Either way, it will always be a win-win proposition.'