When I reviewed my column index last week, I found that I haven’t written about garden planning for several years. New and seasoned gardeners need a review now and then, and that includes me. Building a garden takes a lot of hard work, and it’s not just the physical labor. A lot of forethought and planning must occur before the plants go into the ground. Most of us want to extend our living spaces to the outdoors to provide pleasure and relaxation in a colorful landscape. Plants improve air and water quality; help reduce erosion; decrease air temperature in summer; provide privacy; and muffle street noises along busy thoroughfares. Before you put a spade into the soil, pay attention to the garden location and size, sun and shade, water source, soil pH and quality, and physical restrictions. Is your garden in full sun, or does it have a shady section? Define your space by observing the movement of the sun at various times during each season. The number of hours in sun or shade each day ...