The presence of forms and their interrelationships play a fundamental role in the creation of a landscape. Forms fill the landscape—the round slope of a hillside, the crown of a mature oak, a marigold blossom, a redwood tree, an A-frame house, a topiary garden sculpture, an outline of a skyscraper, a lean-to shed, a drain inlet, a cliff face, the repetition of hill upon hill receding in the distance, the symmetry of a grove of trees.
A successful landscape contains forms that balance and complement each other. Too much height, too many curves, too many rectangles, or other excesses not only may be ugly, but also may make the viewer ill at ease.
Forms also need to relate well according to their size. A circular flower bed measuring 10 feet in diameter might work well next to a circular bed of 5 feet across because of the significant difference in size between the two. Two adjoining circles that are 10 and 8 feet across may be too similar in size to create a meaningful contrast.
In the same way, try to use angles repetitively, but avoid combining too many varying angles in a limited space, which will weaken a design considerably. Stay with angle families, such as 30, 60, and 90 degrees or 45, 90, 180, and 360 degrees. In using contrasting angles, try to tie them into right angles at some point in the design.
Reinforce two-dimensional forms, such as a circular lawn or a rectangular patio, with three-dimensional masses of shrubs and other solid forms. In a circular lawn, for example, make the walk around it circular, too, and plant the trees and shrubs in a circular pattern that accentuates the design.
The edges of an enclosure usually produce a feeling of safety and security. However, a space that is too enclosed will create the uncomfortable sensation of being in a cage. Natural boundaries, such as canyon walls and banks of foliage from trees and shrubs, enable the landscape to project a sense of security. Similar effects can be created by fences.
A space doesn’t have to be enclosed to impart a feeling of protection and comfort. Enclosure may be created from something as simple as an umbrella or a gazebo. Low-mounding shrubs, a rock outcropping, or a depression in the earth caused by the roots of an old tree can seem protective, even though they do not formally enclose anything.
Nor does enclosure have to exist from the level point of view. The boughs of a tree overhead or a trellised vine covering a patio can provide the sought-after security. Enclosure does not actually have to provide safety to be effective. On a pier over water, a heavy chain running between 2-foet-tall bollards can provide a sense of security, when in reality it does little to ensure it. In the same way, the low guardrail along the outside edge of a treacherous mountain pass makes drivers feel safer.
A landscape is significantly influenced by the slope of the ground. Natural or designed slopes affect the way areas are used and the available views.
Adding interest to a landscape, sloped surfaces often provide a sense of enclosure and tend to intensify the play of light, color, and shadow. On the other hand, if a slope gives the impression that something might fall on the viewer, it creates a negative sensation.
Even minor changes in incline can be very noticeable. A 3 percent grade (a ⅜-inch drop for every 12 inches of length) doesn’t sound like much of a slope, but it is the maximum allowable on the interstate freeway system, even as it crosses the Sierra Nevada, the Rocky Mountains, and the Ozarks. Compared with level ground, a 3 percent slope can be as evident as a painting that is askew on a wall. When planned carefully, though, a slightly tilted plane can be appropriate, providing just a hint of enclosure. A battered surface is a wall that slopes away from the ground at an angle greater than 90 degrees. Battered surfaces reflect more light than simple vertical ones and appear solid and stable. Walls and hedges appear to have more solidity if they are given this shape.
Symbolism in Form
Many forms have deep-seated symbolic connotations. Vertical forms naturally draw attention and tend to induce a sense of awe. To capitalize on this feeling, plant a column of trees, place a slender statue in the garden where it will be shown off to advantage, or paint the high wall of a garage to exaggerate its height.
Diminutive and intricate forms, such as those in miniature gardens or the patterns in a detailed pavement design, tend to provoke curiosity. The static nature of a horizontal line, such as still waters, promotes feelings of peacefulness or passivity and gives the appearance of permanence.
Eighteenth-century garden designers believed that geometric forms composed of straight lines were the ultimate expression of reason. A square lawn, a rectangular pattern made of box hedges, angled planting beds, a geometrically inventive patio—all have meaningful impact on a landscape.
Circular forms convey a feeling of closure, and, like islands or eddies in a stream, are complete in themselves. An entryway with a circular design implies that it is a place to wait. When the door opens, the circle is broken along the boundary of closure.
Curves are visual symbols of harmony. A garden has many curved shapes: leaves and pebbles, a billowing mass of foliage, a rolling terrace. When designing a paved walkway or the edges of a narrow planting bed, give them gentle, sweeping motions that flow from one to the other. Projecting and jagged forms suggest dynamism and may imply speed and strength. Depending on how they are used, they may also merely look sloppy. Projecting forms can also imply power. A cantilevered deck, for instance, whose footings are invisible, seems to defy gravity.