Symmetry is balanced and static, and there is more than one type of symmetry. What most people think of first when they hear the word ‘symmetry’ is bilateral symmetry, which is a near perfect, mirror image duplication. Think of butterfly wings- they are bilaterally symmetrical. In design, bilateral symmetry gives a very formal effect. This type of symmetry can be seen in Tudor knot gardens, where herbs were planted in strict patterns and clipped tightly. Symmetrical gardens reached their peak with French formal gardens with their parterres of clipped box, sometimes filled with flowers. Duncan Gardens at Manito Park is a perfect example of this type of design. These gardens are solid looking and the eye sees them as one unit.
More common, especially in home landscapes, is approximate symmetry. In this type of garden, design elements are balanced but not duplicated. Think of a path with an urn on either side of it; the urns are approximately the same size and shape but they have different plants. Or a doorway with a clematis trellised on one side and a honeysuckle vine on the other. There is approximately the same mass, but different colors.
The third type of symmetry isn’t seen very often in gardens: radial symmetry, which is like a wheel with spokes. I’ve seen some herb gardens planted this way, with a different herb in each ‘spoke’, rather like a clock face.
If symmetrical designs are solid and unmoving, asymmetrical ones lead the eye around and create a feeling of movement. Asymmetry does not mean just throwing random stuff into a yard, however. There is still design. In an asymmetric design, you might have a large tree on one side and three medium shrubs on the other. The elements are in no way the same, but they create a balanced picture. Cottage gardens, English gardens and Oriental gardens will all have asymmetrical elements in them. The Japanese Zen gardeners are masters of the asymmetrical garden, where the eye is led from a large rock on one side to a sculpted shrub on the other to some raked gravel.
Many gardens have both symmetrical and asymmetrical designs within them. The front yard may be very symmetrical, which lends focus to the entry to the house, while the back yard may be less formal. Using asymmetry in the more private area where family and friends are apt to sit and spend time keeps the eye from getting bored with the scene. And even within an asymmetrical setting, symmetrical design elements can be used to good effect: a pair of planters on either side of the door, or similar sized shrubs on either side of a bench. Start looking at gardens that you find attractive and look for symmetry and asymmetry; it will help you design a garden you’ll enjoy looking at.