FACTORS IN SELECTING PLANTS
FACTORS IN SELECTING PLANTS
When you choose ornamental plants for your landscape, you should consider three things. First, you should know something about the physical and ornamental traits of the plants, such as their size, shape, type and color. Second, you need to know if the plant is hardy in your area. And third, you should consider how you want to use these plants. For example, do you need a shade or flowering tree, a foundation shrub, accent plants, a screen or hedge, or a specimen for a special garden spot?
PHYSICAL AND ORNAMENTAL TRAITS
Ornamental plants grow to different sizes. You may choose from ground cover plants as small as 6 inches, shrubs of many sizes, and large trees to over 85 feet tall. It is very important to know what size plant you want for the landscape planting. Then choose that size plant from one of the lists in the plant selection guide. The plant selection guide lists plants according to size. It begins with the smallest ground cover plants which grow up to 24 inches high. Then the guide gives small shrubs from l to 2 feet, medium shrubs from over 2 to 6 feet, and large shrubs over 6 feet. Vines and some other plants can be small to large and so are designated variable (V) in the size column. The small trees growing less than 40 feet and large trees 40 feet and up are also listed (note shaded plants in scale drawing at the top of each page in selection guide). The sizes given for these plants are their average full-grown sizes. So when you decide on plants that you want, think about how big the plant will be when it is fully grown. Some trees grow quickly and become large in just a few years, while others grow more slowly and take many years to reach maturity. The plant selection guide makes comments about the growth rate of trees. Remember, however, that growth rate is influenced by many variables, such as soil, drainage, water, fertility and light. The following designations are used in the plant selection guide for trees: S = Slow, up to l2 inches of growth per year. M = Medium, l3 to 24 inches of growth per year. F = Fast, 25 or more inches of growth per year.
Some ground covers are more competitive than others for light, water and nutrients and spread aggressively into adjoining areas. Aggressive growth of ground covers in the selection guide is designated yes (Y) or no (N).
Plants also grow to many shapes. Some plants may grow tall and thin, while some may be short and rounded, and still others are very low and spreading. Many words are used to describe plant shapes or forms. The following designations are used to describe growth habit:
I = Irregular. O = Oval. P = Pyramidal. R = Rounded. S = Spreading. U = Upright. W = Weeping.
When we imagine plant color, most people think green. This is a natural response because most plants are green. But there are many shades of green, such as the bright yellow-green of a privet shrub, the gray-green of junipers, and the dark blue-green of the hollies. And many plants have other colors. The leaf color of many trees and shrubs will change with the season of the year. This adds interest and offers a pleasant color change to the landscape. Many plants have colorful flowers or berries. Examples of plants used for flower color include azalea, forsythia, hibiscus, lilac, spirea and quince. Examples of plants used for their colorful fruit include cotoneaster, holly and viburnum. So, when considering plant color, be sure to think about flower and fruit color along with the foliage color.
Landscape plants need specific environments for best growth. When choosing a hardy landscape plant, consider three questions: will the plant grow in your county of Michigan? will the plant grow in the kind of soil conditions you have? will the plant need sun or shade?
The U. S. Department of Agriculture (USDA) has studied the climates of all areas in the United States. The climates have been put in numbered categories based primarily on minimum low temperatures. The map of Michigan in Fig. 2 shows the three USDA zones for the state: zone 4 (Upper Peninsula), zone 5 (Lower Peninsula) and zone 6 (western and southeastern shores). Find your county and see in which climate zone you are living. Remember your zone because there may be plants especially well suited for your zone and plants that will not grow well there. The plant selection guide will give you this information.
Many landscape plants need specific soil conditions for healthy growth. Most shrubs and trees grow best in well drained, moist soils. It will be very important for you to know what soil conditions exist on your site and how well the soil drains. Poorly drained and soggy soils are not ideal for most landscape plants. With careful plant selection, however, even these sites can be nicely landscaped.
Ornamental plants need light to grow, but some plants require full sun all day, while others tolerate some shade. Still others may require a shady area of filtered light to grow best. It is important for you to know the light condition of the different areas of your landscape so you can choose plants that will grow well in that light condition. It is very frustrating to choose the wrong plant and watch it scorch because the sun was too bright and hot or become weak and spindly because the shade was too heavy.