Where plants are used in an esthetic way they fall into three classes of treatment: first, they may be employed to aid in an architectural scheme, being interesting chiefly on account of their form, as in the carrying out or emphasizing of architectural lines; secondly, for the interest of the plant itself, as is generally the case with exotic material; thirdly, to enframe a view and direct the gaze toward distant prospects or pleasant features, thereby giving emphasis and accent to an otherwise monotonous scheme.
Figure 23. PRIVATE GROUNDS WHICH ARE NOT TOO SECLUDED IN APPEARANCE.
On account of the widely different usage, the characters of economic and esthetic planting must be quite dissimilar. Economic planting, as has been stated, should be so very unobtrusive as even to escape notice, if possible. Consequently plants used in such a scheme will be indigenous to the locality, very quiet in color, and not at all striking in outline. The most successful economic planting is that which fulfils its function and at the same time attracts the least attention.
Esthetic planting, on the other hand, allows greater latitude, and really demands the use of much more interesting material, as the attention is supposed to rest largely upon the plant material and its arrangement as an end in itself. As it has a wider variety of purpose, this will give a correspondingly greater range of selection, and will include the exotic and subtropic plants.
For esthetic considerations the planting is to tell first as dark masses against lighter areas, and this may be termed "contrast of value." This lighter or darker background may be a set of buildings, any architectural work, such as walls, gates, or terraces, or a wide sweep of lawn and meadows in less highly formalized work. The sizes and locations of these masses are determined by the problem in hand, and a successful solution will depend simply upon a nice discernment of their esthetic and economic significance.
In a large number of cases planting is valuable chiefly on account of its silhouette in elevation. This is generally the case in the informal style. In the formal gardens, where parts are filled with brilliant bedding plants, and where the whole scheme is seen at a glance, the plan will be of major importance; the accents alone will appear to any extent in profile, and they are often architectural. The plan will also be of utmost importance if the planting is to be looked down upon from a height, as often happened in the old Italian gardens of the Renaissance, which were almost invariably located on hillsides. It can be said, however, that almost all of these problems where the plan has greater significance will fall within the formal style of planting.
In the informal style the elevation is of greatest importance, and the plan is considered mainly as affecting the elevation. Of course the plan and the elevation are interdependent, and it will be impossible to develop one satisfactorily without the other. Greater attention may be paid to either as occasion demands.
Figure 24. HORTICULTURAL ACCENTS.
Planting problems, as regards surroundings, fall into three large groups, which in turn are subdivided. They are city, suburban, and country problems. At one extreme is complete architectural domination, and at the other the emphasis of natural surroundings.*
In the transition from one type to the other one influence is constantly diminishing as the other grows. In some suburban problems the extremes appear to be rather evenly balanced. Under the city type will come the typical city home, almost exclusively architectural; then the city park, which may be a sort of playground for the children, or a square, either for traffic purposes, or for the display of a monument or a feature to emphasize an axis. This last use is probably seen to a greater extent in Washington, D. C, than in any other city in America. Boulevards and parkways are perhaps the most important field of the landscape-designer in city planting.
Under suburban planting problems will come two classes of homes: the large suburban estate, where expense of layout and upkeep is of no moment; and the small home, such as brings joy to the heart of the commuter. There will also be the large naturalistic and countrylike park, the property of the great city. This park will have varying planting schemes, with much natural planting; golf-links, formal gardens, rocky hills, meadows, curving roads, and the utilization of water as a decorative feature, with its many possibilities in the way of bridges, fountains, and cascades. Parkways of a rather informal nature will be considered here, and also the planting of residential streets as units.
*See Charles Elliott, "Landscape Architect," pp. 266-271.
The country class of design has fewer ramifications, dealing with only two classes of buildings: the large estate for pleasure purposes; and the farm, which is mainly utilitarian. In a country estate the trees and shrubs must harmonize with the surrounding landscape, and this controls in a large measure the selection of the plants used. Plants without pronounced single characteristics are used in large masses, while the more specimenlike shrubs are reserved for the smaller areas. Where trees appear in formal gardens they are considered as architectural features. This refers, of course, to the walled-in gardens, which are exceptions to mass planting. But in the gardens of Italy, where the total area is often as large as a country estate, trees are frequently used as if they were shrubs, on account of the enormous scale of the garden, regardless of the surrounding landscape.
Figure 25. A COLONIAL GARDEN.