The chief reasons for the erection of such screens is privacy, except in very windswept open districts where shelter may be even more important. Often the two go together, and a boundary hedge that gives privacy will also serve as a windbreak, but this is not always the case. A belt of deciduous trees, for instance, makes a fine windbreak, but a garden made in the shelter thus afforded will not necessarily be screened from view.
Another reason for screen planting is that harmonious backgrounds for the various garden pictures can be provided. A light trellis, for instance, separating the formal rose garden from an informal plot of grass and shrubs adds both to the beauty of the rose plot and that of the lawn. Such a screen set between the flower border and vegetable patch makes a decorative background to the flowers, and hides from view the less beautiful vegetables.
It is because division boundaries also form backgrounds, and because their beauty is important to the garden picture, that every consideration should be given to the choice of suitable material. First let us review the various non-living materials of which such screens can be made. First there is wood, in the form of trellis. Trellis can be very open, as in the case of narrow strips of wood nailed to form foot squares, supported by stout posts. This type of open fencing is frequently used for rural gardens, where the vista through the trellis is worth preserving. Similar light oak trellis is used to divide parts of the garden where a close screen is unnecessary, as for example between an orchard and flower garden. It is also employed on walls, where the training of climbing plants direct on to the wall is undesirable.
The common expanding trellis of diamond pattern, though not in itself so decorative as other kinds, is nevertheless useful in places where climbers can be allowed almost to smother it. Another popular type of trellis, frequently used for the upper half of fences between suburban gardens, where a fairly close screen is preferred, is made of inch square pieces of oak nailed together to leave three-inch square openings. Even without the climbers this is a useful screen; stained with creosote, it is immediately unobtrusive, and settles well into the garden picture.
Another type of wood fencing is of closed boards, either set close together, vertically, in the old fashioned way, or woven basket fashion. The woven type is available from several firms, usually in finished sections which can be easily erected by any quite inexperienced worker. There seems to be nothing with which fault can be found in this type of fencing other than its rather high initial cost, for its appearance is good, and it stands up to the strongest gales even in exposed seaside districts.
Stone, bricks, and tiles employed in various ways also come into thelist of materials suitable for boundaries. Stone walls and brick walls are obvious possibilities where cost is no matter, or where these materials are to be obtained without difficulty.And a combination of brickwork and trellis, is very substantial, decorative and effective.
Dry walls, that is walls built without cement, are particularly decorative, since they are built with soil between the stones, and this allows for the planting of the wall with suitable rockery plants. They are most used where there are different levels in the garden, separated by a steep bank, and in this form they are called retaining walls. Retaining walls can, of course, be made with cement joints, and can be quite formal, and constructed of natural or artificial stone, bricks or tiles, without any attempt at floral camouflage.
Stones and bricks can also be used in the erection of pergolas and screens. As a contrast to these various non-living screens and boundaries there are the ordinary evergreen hedges, screens of mixed hedging plants, and several different methods of screening by rows of trees or belts of woodland.
The first matter to be considered by the new garden owner is a suitable type of hedge or screen for the outer boundary of the garden. Naturally this depends a great deal on the size of the garden and on the type of land that lies immediately beyond the boundary. The large estate is often quite suitably surrounded by a simple line of posts with a couple of wires strained to them at distances of 18 in. and 3 ft. from the ground, or by a line of chestnut pales. In the small garden, where other small gardens join it on every side, neither wires nor chestnut paling can be considered sufficient in themselves, but must be supplemented by a fiving hedge. It is possible during the first season to cover a chestnut paling fence with annual climbers, and it would be possible to continue to do this every subsequent summer, but that method is hardly satisfactory since it leaves the gardens open and the paling bare during the winter months. An evergreen hedge which can be clipped back to a narrow wall of green is probably best in all such cases.
HEDGES OF EVERGREEN
Privet, the first and most obvious suggestion, has the merit of being particularly cheap, and it does stand clipping. Also it grows rapidly. It is, however, for other reasons a poor choice because there are other more decorative shrubs available, and because its roots are such drastic soil robbers that a privet hedge will ruin all other plants that are set near it.
Lonicera nitida, the small-leaved evergreen honeysuckle, has all the merits of privet (even its cheapness, since plants cost very little and can be increased with extraordinary rapidity), and it does not rob the soil quite so much. There are, however, a number of other good evergreens that will grow quickly if well treated, and that will stand clipping just as well as privet.
Unless the title deeds of the property specify that a certain type of fencing or hedge is to be maintained, an evergreen hedge is sufficient boundary without chestnut pales. If it is to be planted where no non-living fence exists, but where the site is exposed to keen winds, it would be well to use hurdles or a temporary screen of some kind until the hedge is established. This would make a considerable difference to the rate of growth.
COLOUR IN THE HEDGE
The alternative types of boundary hedges might be given more consideration in new gardens if only because the trim clipped evergreen wall is apt to become monotonous. A hedge of mixed evergreens and deciduous shrubs, specially if there are a good number of showy flowering shrubs among them; makes a very attractive picture. Such a hedge can include ordinary evergreens, and also some of the golden or silver foliaged varieties, shrubs with purple or red foliage or with foliage that changes to these tints in autumn, plants that flower in spring, summer, autumn and winter, and plants that have decorative berries, or brilliant winter bark.
From these few suggestions it will be seen that a hedge of mixed shrubs could, in itself, have as much variety and as much beauty as a mixed flower border, and in fact that is the position exactly. A mixed hedge surrounding a well-kept lawn is sufficient to complete the layout of a front garden, and where labour is a serious problem this helps to solve it in more than one sense. Mixed shrubs need very little attention, whereas a clipped hedge needs attention almost weekly in the growing season.
When planning a mixed hedge it should of course be remembered that some plants are better suited to special soils than others. Rhododendrons, for instance, make an excellent and very decorative thick screen, and form a good boundary hedge. It is useless, however, to plant them where there is chalk in the subsoil.
A flowering hedge made of any one kind of shrub is a very good type of hedge for the not-too-formal garden. Berberis stenophylla, the narrow leaved evergreen barberry, is possibly the best of all plants for this type. It is thick and impenetrable, spiny enough to keep out dogs and prevent much wanton damage. Its arching sterns are quite attractive all the year round and really spectacular in their beauty during April, when they are covered from end to end with small golden blossoms.
Since the planting of a ‘boundary hedge is likely to be the very first garden operation carried out by a new owner, it shall be described here in detail.