Introduction
Most of the amenity tree and shrub species used in the United Kingdom can be reliably and easily transplanted, provided:-
the planting soil is properly prepared, drained and will support the chosen plants
the plants are healthy and have been carefully lifted, stored and transported as relatively fragile living organisms
the planting is done correctly and in the right season
the planting is followed by proper after care.
For large-scale planting the ideal conditions are difficult to achieve and there are often large numbers of plant failures or very little growth for the first few years after planting.
This code of practice shows how this can be avoided and recommends the essential minimum standards that are required to achieve satisfactory planting and establishment. For the most part they are based on the accumulated experiences of the horticultural and landscaping industry and supplemented by an increasing body of scientific and systematic research, all of which support the following general principles.
Hardy nursery stock plants, even when they are dormant, are living organisms and although they have a certain “shelf life” they will quickly die if they are not properly stored or handled. There is evidence that after bad commercial practice some plants may be incapable of surviving even before they are planted.
Small stock, seedlings and transplants will generally transplant and establish better than standard trees and other large stock. However, they obviously have much less early impact in a landscaping scheme and they are rather more susceptible to root drying and failure if they are not handled correctly, and to damage by weeds and rabbits.
Root drying is the most common source of plant failure and lethal drying can take place very quickly if lifted plants are left unwrapped. Root dips may provide some protection against drying but are not a substitute for, or provide any significant advantage over proper handling and root protection.
Black polythene bags are an essential aid for keeping bare roots moist. However, in sunlight they will rapidly absorb heat and thus warm up any plant material inside to potentially lethal temperatures. Co-extruded black and white polythene bags, though more expensive, do not suffer from this fault and are strongly recommended as the best practical protection for lifted bare root plants where shaded storage is not available.
Small stock in particular is sensitive to rough handling and the physical shock of repeated dropping or crushing will significantly reduce the survival rate.
Cell grown stock, usually small seedlings, are much more able to survive poor storage and handling but do not necessarily show any distinct advantage over well handled bare root seedlings.
Container grown plants are a much more reliable form of planting stock and can be successfully planted at almost any time of the year, if adequate watering is available. They are, however, considerably more expensive to grow and transport.
At all stages between lifting and establishment, plants are susceptible to rodent damage and protective measures should be taken.
Even the best quality and carefully handled stock will not flourish in waterlogged or infertile soils (apart from willows and a few other species). Adequate drainage and soil preparation are therefore just as important as plant handling.
Finally, professional after care is essential if the plants are to survive and establish beyond the planting stage. In particular it is important to ensure that appropriate watering is available in dry spells and the competition for soil moisture is reduced by rigorous weed control.
In attempting to give concise guidance a number of aspects of good management practice have only been touched upon or have been omitted. Further details for specific sectors of the landscape and forestry planting industry can be found in the publications that are listed at the end of this section.
Similarly, the formal requirements of contract arrangements are not covered in the booklet as in many planting schemes the number of parties and the links between them can be complex. However, it is essential that the contractual responsibilities are clearly defined if cost effective results are to be obtained.
Finally, although this booklet is mainly directed towards hardwood trees and shrubs, similar recommendations also apply to herbaceous species.
March 2002