How formal should a hedge be to work with the style of your house and garden? This guide will help.
Hedges are living walls. Formed by shrubs or small trees, they can be used to block views, delineate boundaries, create garden rooms, or serve as a backdrop for other plantings. Depending on the plants you choose, hedges can be formal with a mass of green foliage or wildly exuberant and covered with blooms.
Foliage, whether accompanied by flowers or not, defines hedges. Plants that make good hedges have close-set branches with lots of leaves that start at ground level and continue to the top of the plant.
Most hedges are evergreen. If you don’t mind or actually want bare branches or complete dieback in the winter, though, you can find good hedge plants that are deciduous.
Hedges fall into three categories: formal, semiformal, and informal. Each has its own place in garden design, and each has its own requirements for pruning and training.
Formal hedges are the neatly trimmed, symmetrically shaped perimeters that most people first think of when they hear the word “hedge.” These hedges are created from a single species or variety with a dense growth habit of small leaves. They can range from just a foot high to well over 6 feet tall. The overall impression is of a solid block of greenery rather than a single plant.
Boxwood (Buxus) is the classic plant for a formal hedge, but other choices include barberry (Berberis), hemlock (Tsuga), holly (Ilex), and yew (Taxus). Bamboo can also be a formal hedge choice, but you will need to buy a clumping variety and keep it well in check.
Semiformal hedges are also usually composed of a single species or variety of plant. The difference is that the leaves are generally larger and stand out as individuals rather than a mass, and the overall plant form is somewhat less rigid. English laurel (Prunus laurocerasus), firethorn (Pyracantha), and photinia are all good choices.
Rather than having a rigid, geometric shape, informal hedges are casual, creating a barrier that may change from tall to short and from wide to narrow. This style works well in natural and cottage gardens, with their emphasis on loose form and a mix of plants. In fact, mixing a number of different hedge plants is a good way to create an informal hedge—a good choice for flowering plants, as they can be pruned and shaped so flower production isn’t inhibited.
Small, informal hedges can be created from lavender (Lavendula) or santolina; medium informal hedges may consist of junipers or weigela; taller hedges might be comprised of oleander (Nerium oleander), osmanthus, or photinia.