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The second law of composition is unity—oneness—all parts of a design uniting into a single major idea with individual identities merged in the greater whole. A simple experiment will indicate whether your design has unity. On your plan, cover up certain elements in the design, perhaps a bed or border, or a group of plants. Does the design suffer from the subtraction? If not, the part covered is unnecessary and tends to destroy unity. In extreme cases of bad composition you may find that any section can be removed. If this is so, discard the whole scheme and try again.

The same test for unity may be applied to smaller garden pictures in their frames. Can this or that plant be removed without damaging the picture? If so, the group has not been tightly enough composed.

How to achieve unity is, however, more important than how to detect its absence. In the garden pattern all parts of the design, path, bed, or border, must be interrelated. The whole must hang together. Anything extraneous detracts from the quiet satisfaction of a unified scheme.

In planting likewise, every group must play its part and be related to the whole. The small garden can successfully present only a single idea, a single picture. Avoid saying too much. Larger gardens of more scope can accommodate several pictures but they must not compete. They too should be part of a greater whole, complete in themselves but integral with their surroundings.

Many gardeners, especially plant enthusiasts, put too much emphasis on small, intimate groupings, as a few hemerocallis with a clump of phlox, a delphinium with a lily or two, a single pansy with a group of scillas. Such precious groupings have a place in the composition only when they play a part in the larger scheme. They have little value as individual bits. In fact they are generally lost unless repeated in a sequence. If you are tempted to indulge in this sort of thing, apply the unity test frequently to your garden. When you find that a certain group does not strengthen the picture, either discard it, or amplify it so that it does count in the general scheme.


Those who so love plants that they incline to strive for too many in too little space, should try to be aware of unity at the very beginning of their garden planning. An overcrowded, heterogeneous collection of plants, no matter how beautiful as individuals, will not produce a unified scheme. No less an authority on garden design than Gertrude Jekyll has said, "I am strongly of the opinion that the possession of a quantity of plants, however good the plants may be in themselves, and however ample their number, does not make a garden. It is only a collection."

With such a host of fine plants available the beginner's "must" list is often tremendous. No one garden, unless it is acres in extent, could hold them all artistically. The task of reducing such a list is a hard one that must be undertaken before any plants are ordered. There are several methods of elimination. All plants do not thrive in the same soil. So the soil of your garden will help to govern your choice. Is it dry, wet, or average? Is it acid, sweet, or neutral? Is the garden in full sun, partial shade, or all shade? These factors are important to the growth and well-being of plants, and each of them limits selection.


Since ecology is the study of plants in relation to environment selection based on habitat might be termed the ecological method. Elsa Rehman and Edith Roberts wrote helpfully on this subject in American Plants for American Gardens. They concluded that most plants live in societies based on similar physical requirements. Therefore a degree of garden unity can be secured by selecting plants according to environment.

Closely connected is the matter of climate and exposure. Today we use plants native to Asia, South Africa, South America, Europe, and the many sections of our own country too. This does not mean that they will all live and thrive in our gardens. To be intelligent about plant selection we need to know fairly exactly for a given locality the date of the last hard frost in spring, the first killing frost in autumn, and the lowest degree of temperature in winter. This information has a bearing on the varieties of plants we can grow. Most garden encyclopedias and dictionaries now have a geographical chart indicating climatic zones. Some garden books and catalogues also note degree of hardiness, for example, "Not hardy north of Philadelphia except with winter protection." No garden is successful if a large amount of the material in it is of questionable hardiness. Nor will it look like much in winter if it is full of trussed-up specimens, mounds of salt hay, clutters of leaves, or masses of evergreen boughs protecting tender plants.

Bad as this is artistically it is even worse financially for many of the more exotic plants, which are not cheap, often succumb the first winter, and there is added disappointment and a last-minute rush to fill empty spots with something more durable. We were all made conscious of hardiness a few years ago when an excessively cold winter robbed many northeastern gardens not only of all tender plants but of many long considered hardy. Such winters are not normal but occur often enough to make it foolish to use plants of doubtful hardiness in prominent places.


Unity may also be obtained by restricting a garden to a certain class of plants—perennials, roses, or annuals. Annuals and perennials can be used together, but, like roses, generally do better separately, and in gardens of one classification there is a greater feeling of oneness than in a garden that is mixed. Restrictions to a limited number of colors and to certain seasons of bloom also tend to cut down plant lists and make them manageable.

Color can be utilized to create unity throughout the growing season. The color of flowers must be properly blended and displayed in large enough masses to be telling, but this is no plea for one- or two-tone gardens. We feel that the blue, white, yellow, or pink garden is a step in the wrong direction because it limits possibilities too severely. Besides working out such color schemes is a terrific chore and many times results in a garden that though unified is monotonous.

We do believe, however, that the color plan of a garden should so overlie the pattern that the beds are pulled into a unit and become parts of a single seasonal picture. The difficulty is that color in our climate is of such short duration that it is necessary to plan for many pictures to follow one after the other, to have, in other words, succession of bloom.

It often helps the beginner to limit himself to fewer plants, at least until experience makes possible the effective handling of a more varied list. The small garden looks better if it has only, say, ten different shrubs and small trees for background and enclosure, not more than fifteen perennials, and possibly five annuals.

plate 8a
Plate 8a. A Garden Picture for Each Season: Early Spring - Early Summer.
plate 8b
Plate 8b. A Garden Picture for Each Season: Midsummer - Fall.

When a long list of plants has finally been brought within bounds, the principle of unity needs to be considered in placing the selected material. Broad masses, or large groups of plants repeated in different parts of the garden have a pleasantly unifying effect. Here again the urge to have a great variety should be curbed. If a plant is worth using at all, it should be worth using in large enough quantities to be effective. One lily, one phlox, and three zinnias make a group, but such a small group that it produces no harmony, particularly when spotted here and there in the border. The common tendency to buy plants only by threes is equally bad, though better than buying "ones." A garden planted in such a manner, and many gardens are, cannot help looking busy.

Small gardens cannot accommodate more than one or two related pictures at a time. Limiting the pictures in bloom at the same time is another way of securing unity. This does not mean that only one or two spots of color can be used. The same arrangement should be repeated several times along the garden path, balanced across the main axis, or repeated in the four sections of the central-motive pattern. Usually we have found that a single broad arrangement can be employed satisfactorily in this manner for each of the periods of the garden year; early spring, spring, late spring, early summer, summer, midsummer, and autumn. This method gives sufficient bloom, good succession, and helps create unity.

All this discussion of unity really boils down to a question of simplicity. Simplicity is not a principle or a rule, but a highly desirable objective. The smaller the garden, the simpler and more straightforward it should be. Such decorative elements as statuary, benches, arbors, and bits of trellis are hardly suitable unless they serve a definite purpose in the design.


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