Most people start with color, texture or form. But it is light, water and temperature requirements that should lead the way if you want to avoid a lot of unnecessary pruning, staking and even killing of innocent plants. Before you go to a nursery or start circling items in a catalog, get outside and watch the light for a day. The morning light might be pleasant but the afternoon light hot. A spot near a wall might be shaded but is getting light reflected off the wall. Soil moisture varies, too, with some areas drying out quickly and others staying moist longer.
Don’t try to remember what each plant likes. Instead, try to remember groups of plants that like the same things. For example, which plants like dry soil? Which can handle a bit of flooding now and then? Which need to be constantly moist? Never judge soil moisture by eye alone, as the surface can be deceiving. For example, many people plant a full-sun plant in partial shade, thinking it looks “sunny enough” here, and the plant does poorly and doesn’t bloom. Novice gardeners then think it might need more fertilizer, but there is no amount of fertilizer in the world that will make up for a lack of light. Most of the time, what the plant really needs is to be transplanted to a different spot.
Shape and form are just as important as flowers. Think about how large the plant will grow after several seasons, and what kind of spread it will have. Plants that have short-lived bursts of color in the spring can be wonderful to look at, but they leave a bare spot for the rest of the year. Think about how your garden will look in winter, when the flowers are gone, and the leaves are off the plants. Evergreen shapes, grasses, and shrubs will give the garden structure during the off season. Without these bones to the garden, it will feel like you have no garden for 6 months out of the year. You can add seasonal accents around your structure that bloom for a month, but with the structure still there, it will be much easier to work with.
Just 15 minutes a day devoted to studying the shapes and growth habits of two or three planting candidates, then determining where they would grow naturally in your design, is a great way to train your eye to see the mature forms — draw them on your plan at the size they will grow to in the garden, not as they are growing in pots — to prevent crowding, so that you don’t end up with too many plants for the space you have. If you can’t visualize, plant less now and know you have space to plant more later. It’s always easier to manipulate vacant soil than it is a bed of struggling specimens.
Eventually, you choose plants less by desire and more by understanding the site. You begin to see the garden as a whole organism instead of a series of individual ornamentals. When you match the conditions with the needs of the plants, things seem to grow without effort, and you don’t feel the compulsion to tinker as much. You let the garden evolve from year to year.
