The process of designing with plant materials during preliminary design is one of studying and using plants in a broad-brushed manner. Plants are located to fulfill architectural, aesthetic, engineering, and environmental functions while complementing the overall intended character and style of the landscape design. Consideration is also given to the desired visual characteristics of plants, including size, form, foliage color, and foliage texture. At the conclusion of preliminary design, plants should be located in general masses within the design and identified in generic terms such as “shade tree,” “low evergreen shrubs,” or “perennials.” The identification of plant ma-
terials by specific common or botanical names usually waits until the preparation of the master plan.
It is critical to understand that the process of designing with plant materials is an integral part of the overall design process. Planting design is not a separate activity that occurs by itself, nor is it simply the procedure of picking plant names from catalogs or other available sources. Plant materials should first be studied during the development of functional diagrams and then in all of the following steps of the design process. During preliminary design, plants should be considered in terms of both form composition and spatial composition. The design of forms on the ground plane and the related consideration of three-dimensional space must occur with plants in mind. For example, Figure 11—50 shows two alternative proposals for a backyard (also see Figure 11—32). In each instance, the ground forms, space, and plant materials are all coordinated and studied simultaneously. Note how the ground forms and tree locations reflect each other in all of these examples.
To organize and select the plants in preliminary design, the designer should start with general concepts and then add detail through a series of refinements. The first step should be to establish the structure of the planting design in a loose, freehand drawing (Figure 11—51). At this stage, the main concern is to determine the location of trees, shrub masses, and general ground cover areas for definition of space, shade, screening, visual accent, and so on. Trees are usually located first because their relative large size has the greatest impact on the design. Next, shrub masses are added to complement the trees and to fulfill additional design objectives. Again, this should be done in direct coordination with form and spatial composition. One may need to work back and forth between ground forms and plants, first adjusting one, then the other, so they work together compositionally.
The location and arrangement of plants must be directly coordinated with the form and spatial composition of a design.
First, establish the overall structure of the planting with trees and general shrub masses.
The second step of planting design builds on the first by studying the organization of plants in slightly more detail (Figure 11—52). The location and size of trees are refined as necessary. In addition, shrub areas are subdivided into generic types such as “deciduous,” “coniferous evergreen,” and “broad-leaved evergreen.” Ground cover areas are likewise given more specificity by identifying general areas of ground cover, perennials, and annuals. Shrubs, ground cover, perennials, and annuals are graphically shown only by outline. The height of these plants is also studied and proposed at this stage, allowing plants to be given labels such as “tall evergreen shrubs” or “small ornamental tree.” The intent is to visually link (interconnect) the primary plants and to provide a composition of varied heights. The designer has now established the skeletal framework of the planting design.
The next step should be to study the relative foliage color and texture of the plants. This can be done by adding graphic value with lines or color to the drawing in Figure 11—53. The objective is to create a tapestry of varied colors of green along with a range of textures. Plants with dark green foliage are typically used as backgrounds or as visual “anchors” below the canopy of lighter or more open deciduous trees. Plants with light green foliage are best used as foreground plants or as contrasting elements in relation to darker ones. Coarse-textured plants are commonly located to serve as accents while fine textures are used for contrast. After completing this step, the designer has defined the visual characteristics (size, color, and texture) of all the plants in the design and has coordinated them to fit appropriately into the overall scheme. It should be pointed out that specific plant names have not been considered—only plant characteristics.
The final step in the planting design process is to complete the drawing of the plants on the preliminary design (Figure 11—54). All the primary plants, such as trees, are drawn as single plants or masses of single plants, while shrubs are shown as large undifferentiated masses. An attempt should also be made to use graphic symbols that represent the visual character of the plants. For example, dark foliated plants should ideally be drawn with a darker value while coarse-textured plants can be given a
rougher outline. Nevertheless, good graphic techniques should prevail, making it likely that not all characteristics can be illustrated. As is typical of preliminary design, specific botanical or common plant names are not identified or included. This occurs during the development of the master plan.