Give some thought to building materials, then to the interior style of the house itself. All materials, to a degree, dictate how they should be used. In planning your garden try above all to avoid mixing materials and styles as it is rarely successful. Plants too have very definite characteristics and the selection of them will certainly influence the overall look of the garden. But the choice of materials must come first when establishing the layout and basic style.
Materials for gardening
The character of your town or village will have developed partly from the materials available at any one time and the way in which it was possible to put these together. Look at the older buildings in your area which will probably be in the local material. The local material is usually the cheapest and, if not avallable new, can often be bought second-hand. Many areas have no local rock, in which case the construction traditionally would be in wood or where clay was available in brick, though today more and more houses are built of concrete.
Garden to match your house
Now consider the interior of your house; it will, of course, be dictated by family use as well as aesthetic considerations. It is equally important that the style of the garden is in keeping with the inside if the house and garden are to be seen as a whole. Not only does the house lead out to the garden and thus form a unit in the physical sense but the garden can usually be seen from the windows of the house and should harmonize with the interior as much as possible.
In very broad terms, the rustic effect of country-style furnishings would call for a garden with a sweep of lawn and planting in herbaceous borders while a sophisticated modern interior will be complemented by a more streamlined type of garden with a stronger use of plant materials, concrete and cobble. Traditionalists will want a gentle, harmonious layout, with perhaps stone, soft curves and a glint of water. Many other types of house, such as the summer house retreat, the seaside villa and the town house all have particular characteristics which call for a particular style of garden.
Once the fundamental style of your garden has emerged, from a consideration of building materials and the interior look of your house, from then on each individual's garden is unique. Its character grows partly out of practical solutions to practical problems and relates also to the specific functions the garden is expected to perform. At a later stage planting will of course flesh out the bones of your garden and give it finally a very particular feel.