Renovating an old garden site

Press, 5 December 1978, Page 16

Renovating an old garden site

LANDSCAPING AT HOME

By

Gilbert Brakey

Many people choose to buy an established house and garden with the idea of renovating both to suit their particular requirements.

Often an established site will have many features which can be retained and which will warrant protection during any development. Indeed, it is most important before embarking on any large-scale alterations that you make a careful study of all those things which can be highlighted or exploited by a new design.

The best idea is to make up a list and attach this to a plan of the site. Once you have reached a decision on the features to be retained take steps to ensure that they are adequately protected. The entire design will more than likely hinge on the site features that you have chosen to protect. It may be necessary to change your original ideas in order to accommodate protected material on the site, particularly if you plan to extend the house, build a garage, or construct new fences, etc. So prepare to be flexible in your design. If contractors of any kind are involved it would be wise to include a section in the contract documents which will control their use of the site and ensure that no damage will be incurred during the contractor’s operations.

This type of integrated planning certainly has many advantages. It will mean that a landscape programme can be planned with the nature of the site in mind, consequently reducing over-all costs, allowing more money to be used for new work, and not spending needlessly on repairing damage to the site.

Mature plantings should be retained wherever possible as they will provide immediate pleasure and shelter. Further new plants can then be more easily established within the protective environment created by the existing plants. Every effort should be made to protect any worth-while trees and shrubs which exist on the site. In particular careful attention should be given to trees.

Even a small tree may have taken 10 years or more to reach its present hight. It is all too easy with a few quick blows from an axe or a minute or two with a chainsaw to undo many years of work. Any tree to be retained should be checked over carefully for disease, broken or weak limbs; then take whatever steps are necesary to rectify the problems found. If you are uncertain what to do call in a qualified tree surgeon to attend to the tree.

Very few trees need to be removed because of poor health, providing the

problem is cured and not allowed to continue unchecked. More and more people today can appreciate the value of trees in their gardens and very few would wantonly destroy them. It is unfortunate, however, that they may be destroyed unintentionally through neglect or changes of their environment. During a tree’s growing period it adapts

to the particular conditions of the site and itself contributes to the surrounding microclimate. A tree or shrub can suffer a drastic set back by rough treatment, such as careless removal of roots or banches, by indiscreet “pruning” techniques or damage caused by machinery.

Scars and breakages permit the entry of insects. water and numerous diseases which attrack the tree, resulting in poor health or eventual death. To ensure that, damage is prevented, any established tree and shrub plantings should be effectively roped or fenced off during the course of construction work.

There are also less obvious actions which can cause damage to a plant and these may be caused by compaction of earth around the root system, by machinery, the altering of levels around the tree, and the clearing of wind protective plantings, which consequently alters the microclimate around the particular plant to be saved.

The best thing to do is to avoid disturbing the roots of a tree, but there are times when this is unavoidable. If, for instance, you find it necessary to lay pipes close to a tree, avoid cutting any roots over 75mm in diameter, and ensure that larger roots are sealed after cutting with a pruning wax to assist in healing.

When opening up the trench leave as many roots as possible intact, for the pipe can be laid underneath them. The roots should not be left to dry out; cover them with wet sacking. Where pipes run close to tree roots it is wise to have the pipes encased with concrete to avoid them becoming blocked later with roots. This pars ticularly applies to sewer lines.

As a rule no more than 5 per cent of a tree’s roots should be removed.

Changes to the soil levels around a tree’s feeder roots, which are

generally fairly close to the surface, can seriously affect the health of a tree. If the soil is removed the feeder roots will be exposed and cease to function.

On the other hand if the soil is build up around the trunk of the tree essential oxygen will be prevented from reaching the roots, causing them to die back. Feeder roots are mainly found at the “drip line” on the perimeter of the tree canopy, as this is naturally moister than directly underneath the tree.

Observe how trees and smaller plants grow in their natural habitat. It is unusual for a tree to grow out on its own — normally it would be found in association with other trees of its kind, and shrubs, graded in size to provide effective resistance to the prevailing winds.

Construction materials chosen for an established garden should be selected carefully so as they blend harmoniously with the house and other structures. Fences and paving, for instance, can reflect the materials which have been used in the house.

Whether you are designing for an old established garden or a completely new garden, the basic principles of good garden design should still be applied.