Vines constitute a small but important group of plants possessing certain characteristics which are very valuable for use in landscape design. The annual vines develop to maturity and must be started again each season from seed. Perennial vines, once firmly established, continue to increase indefinitely, at least during a period of years. Many vines, such as the wisteria and ivies, are seen on buildings hundreds of years old and, in general, the average long-lived vine will outlive its period of usefulness on any building, especially on wooden structures, which are subject to decay and to periodical repairs.
To many people a "vine is a vine" without any differentiation as to its usefulness. As a matter of fact, vines may be divided into certain definite groups which are valuable for different purposes. The knot-weed, honeysuckle, and climbing roses represent a group which are very desirable for their flowering effect. It often happens that vines are desired, not so much for their screen effects as for the effect of producing flowers within a limited space, and thus adding spots of beauty to otherwise unattractive and monotonous surfaces.
It is quite necessary in selecting vines for use on brick work, stone and masonry surfaces, that the method of growth of such vines should be fully understood. Those vines which grow upon fences and lattice work are either scramblers or twiners or they grow by means of tendrils, as do the Virginia creeper and the grape. None of these vines are adapted for use on brick work and masonry surfaces. There is a group of vines which grow and cling to these surfaces by means of little growths, at intervals along their stems, the tips of which, as soon as they come in contact with any surface, produce a sticky fluid that immediately "cements" the vine to the wall. In the case of the Boston ivy the little tendril, at the tip of which is the adhesive substance, has a tendency to contract in the manner of a twisted cord and thus pull the stem closer to the wall. This is a peculiar provision of nature. This list of vines is comparatively small and is represented generally by the Boston ivy, English ivy, and the climbing evonymus or Japanese evergreen ivy. The ivies in general are much more rapid growers than the evonymus.
There is one group of vines which possesses a very vigorous climbing habit and develops a heavy foliage, such as the Dutchman's pipe, Virginia creeper, kudzu vine, and the knotweed. Of this list of vines the American bitter-sweet and the Dutchman's pipe possess an interesting heavy foliage.
Vines are valuable not only for their flowering effect but they are valuable for the effect of their fruit also. Some vines, such as the matrimony vine, with its brilliant orange fruit, and the American bitter-sweet, with its red and orange fruit, together with the Virginia creeper, with its interesting blue fruit, are valuable in a landscape setting far into the winter months.
Oftentimes local conditions require the selection of a permanent vine with a fast growing habit. It may not be advisable to use annuals, but rather to use a more permanent type and accordingly the designer resorts to such plants as the Dutchman's pipe, the knotweed, and the kudzu vine, which under normal conditions will make a growth ranging from ten to forty feet in a single season. The knotweed is not entirely hardy in severe exposures and the young plants should not be planted in the open ground before the latter part of May.
In general, vines fill a gap in the field of landscape planting which cannot be filled with shrubs. Where conditions develop in which only a limited space is available for foliage, flower and fruiting effects, vines must be accepted as the logical solution of the planting problem. A quite common mistake in the use of vines is to select types which are too fast growing or which are not adapted to the special purpose for which they are used. A common mistake also is that of covering interesting pieces of brick work and stone masonry with vines which completely obscure the beauty of the architectural detail. Vines should be used on buildings to emphasize the architectural detail; otherwise there is little use in spending sums of money to produce added beauty in architecture if such detail is immediately to be covered with vines. We often see an elevation of a house on which appears a chimney with the entire surface of the house and chimney covered with vines. In such instances the vines, for the purpose of architectural composition, should be planted only on the chimney or on the surfaces at either side of the chimney and not on the chimney.
Many persons object to the use of certain types of vines such as the Virginia creeper and the ivies, which form a beautiful roosting place for sparrows immediately opposite sleeping-room windows, and for such locations a type of vine similar to the evonymus should be used, which does not provide a shelter for these pests.