Using Trees and Shrubs
Walls of Green
The care we take in planning the walls of green about our outdoor living room will contribute greatly towards its charm and beauty. It is a good idea to remember that the materials we use are growing things. All varieties have certain natural tendencies and individual habits which identify them and make them better suited to some uses than to others. Similarly, growing conditions vary greatly from region to region.
Once we have determined the form and type of planting material desired, it is easy to select from a nursery catalog the tree or shrub corresponding in character with the desired planting. Or again, we can present our roughly sketched idea to the landscape artist or nursery worker and he or she can assist us in choosing the best plant for each location in our outdoor living rooms.
Walls of green fall into two general types according to the way plants are used and maintained -- informal and formal. For informal types, various groups of plants are irregularly arranged in a border and allowed to grow naturally, creating an irregular wall free in spirit. In the formal type, only single varieties of plants are planted in numbers and in a row. They are later trimmed to a definite shape establishing the lines of the adopted plan. The formal type of wall is commonly spoken of as a hedge, although hedges left untrimmed may take on a very informal character.
The general scheme adopted in your outdoor living room, whether formal or informal, will determine the type of plant walls required and the extent to which they are used. In both types of outdoor rooms there may also be need for a combination of both formal and informal plant walls. In an informal room, it is often desirable to plant a formal hedge along a walk or boundary. In fact, where a solid dense wall is required and there is little space available, the hedge, either trimmed or untrimmed, is generally the best answer. In the formal outdoor living room, unless an effect of strict formality is desired, the introduction of some informal planting in appropriate places will tend to make the room more charming and inviting.
In planning the walls of green for an outdoor living room, both the plan and the elevation or skyline must be considered. If one first sketches a plan for the outdoor room, it is possible to study the planting that makes up the walls much as one would study the elevation of a house.
Planning the Informal Wall of Green
As privacy is one of the first essentials in the outdoor living room, we must consider our border from the standpoint of screening (blocking out undesirable views from the inside and shutting out the view from the outside) as well as to provide an interesting skyline.
By using high growing plants in some places and low growing plants in others, as well as interspersing a tree or two for added height and variation, a very pleasing effect can be secured and unpleasant views entirely blotted out.
In planning space in the outdoor living room for our shrub border, do not allow over four feet of width for an informal border of medium height, with untrimmed shrubs planted in a single row. If the plants are staggered, or arranged zigzag, allow up to seven feet. Where perennials are to be grown in front of shrubs, allow at least six or seven feet minimum for the combined shrub and perennial growth. The maximum width of the bed is naturally greatest at the corners of the outdoor room and likewise at these points it is often desirable to have the greatest height. The higher the shrubs grow, the wider the border should be. Borders may be widened as the plants develop.
In outdoor living rooms of limited area, it is impossible to achieve a great degree of freedom with shrubbery border. For this reason, the more formal and simple development is most suitable for the very small area. A hedge, for instance, can be grown six feet high and require only two feet in width. An untrimmed plant growing six feet high will often take up six feet of ground space.
Where a dense screen is needed to a height or six feet or more and only six inches or a foot of space is available, use a trellis or fence support and cover it with vines.
It is important to keep in mind that plants are not like chairs and tables that can be set in place and then forgotten. Their growth and change must be considered.