How to plant a tree
Trees are living things and, like all other living things, need care and attention if they are to flourish. These practical hints will help to ensure that the trees you plant will survive and give pleasure for years to come.
Where to plant trees
There is such a wide range of trees species to choose from, it is possible to select one to suit virtually any situation, ranging from small gardens, large estates, factory sites to derelict areas. Those who wish to help provide more trees but have no available space may wish to plant on village greens, school grounds, city farms and road verges, or in places where the trees will hide ugly views as well as in the countryside. In such cases, always ask the local council or the landowners well in advance for permission and do not proceed without their written consent.
Which trees to plant
Many tree nursery catalogues list a large variety of types and sizes of trees. Be careful to select a species that will give you the desired effect and will grow in the existing soil and climatic conditions. Before making your choice, please check the ultimate height that the tree is likely to reach. In small gardens or close to buildings the smaller types should be selected; the risk of root damage to buildings must also be considered. But where there is plenty of space around, you can plant the larger types of tree species. Look to see which types of trees grow well in your area and this will give you some guidance. Your local garden centre may also be able to advise on suitable species.
Sizes available for planting
Trees are available from nurseries in a wide range of sizes. The smallest are transplants and whips, which will be from 30 - 150 cm in height. They are easy to move and should grow quickly. They are especially suitable for planting in a new area of woodland, and are usually seedling raised. Next in size comes the feathered trees. These have branches to ground level and will therefore need shaping, but they can reach a height of 1.5 - 2 m. Trees grown to this stage in pots (container-grown) are often available from garden centres: this method has the advantage that the roots do not have to be disturbed when transplanting. Such trees are also still not too large for easy transportation by car.
At the top end of the scale are standards, having a clear stem of 1.5 - 2 m and an overall height of 2.5 m or more. Standard trees are good for creating immediate visual effect. They do, however, suffer greater shock during the transplantation process than smaller trees and therefore require more time and care to establish successfully.
Most deciduous trees can be transplanted without soil on their roots (bare-rooted), but evergreens and some more difficult deciduous species should have their roots in a ball of soil held together with hessian to protect the young roots and hold the soil around them (root-balled).
When buying a tree, always check that it is in good condition with a strong straight stem and a well-balanced branch system. It is important to know that if you are buying a bare-rooted tree, you must make sure that it has a good fibrous root system, which has been kept moist. Root-balled trees should have moist soil and a firm root ball. The tree should be dormant, that is, new growth should not have begun to appear. If a container-grown tree is found to have thick heavy roots coiled and deformed in the pot or protruding from the holes at the base it should not be selected, or if the trees were already delivered by or collected from the supplier, it should be returned to them.
Buy locally wherever possible, and protect the tree from drying out during transport. If you have a tree sent to your home, then you should not accept delivery if, when it arrives, the roots are not protected and wrapped, or the plant is seriously damaged.
If a tree cannot immediately be planted in its final position then (unless it is in a pot) dig a temporary hole for it, cover the roots with soil and keep it moist.
When to plant
Bare rooted and root-balled deciduous trees should be planted in the period after their leaves have fallen in the autumn but before the buds begin to break in the spring. This varies somewhat from year to year and from one part of the country to another, but the planting season normally runs from October/November to March/April. The Tree Council celebrates the start of the planting season each year with National Tree Week. In the case of evergreens, planting may be undertaken between September and April. Trees should not be planted if the soil is waterlogged or frozen.
Container-grown trees can be planted outside the ‘dormant' period described above provided that, if the weather is dry, ample water is applied.
Look carefully at the type and condition of plant growth already on the site as it will reflect the soil conditions. Money and time spent on site improvement before planting are well spent. Compacted soils drain poorly, are badly aerated and can be very dry in the summer. Improvement after planting may not be possible.
If the soil in the area is of good quality it is only necessary to dig a hole as large as the spread of the roots. On poor, badly drained or shallow soil it will be necessary to improve the planting area by digging a hole at least 1 m across and 30 cm deep for trees around 2 m height or 60cm across and 30 cm deep for 1 m high trees. On sites with poor quality soils, it is best if this preparation can be carried out some months in advance of the actual planting process. The hole is refilled with new soil that can be allowed to settle and then more soil can then be added when the tree is planted if needed.
Whatever the size of the hole, an area of 1 m diameter around the tree should be cleared of grass and weeds. Break up the compacted soil around and under the hole to improve drainage and aeration of the roots. Don't just ‘tickle' the base of the pit dug for the roots before planting: penetrate further with a crowbar to loosen deep compaction and to improve drainage. This helps to stop the tree getting root bound, as with a plant in a pot. It is important that water does not accumulate in the planting pit as trees can drown. If planting in a grassed area first remove the turf and, when the hole is dug, place the turf with grass down, in the base of the hole. The soil to be used for planting must be in a friable condition. If the soil excavated from the hole is poor, it can be improved with bone meal and with organic material such as leaf mould.
Insert stake if required (see next section)
Remove any wrapping or container from the tree, but for root-balled or container-grown trees do not disturb the soil around the roots
Inspect the tree and remove any broken or damaged twigs and roots
Soak the roots well before planting
Check the depth of the hole (the union between the root and the stem must be at finished soil level) and adjust if necessary
In the case of bare-rooted trees, space the roots out carefully and enlarge the hole if necessary to avoid bending any roots
With one person holding the tree, a second person can put soil over the roots
Shake the tree gently up and down, so that the soil filters through and around the roots. Then firm the soil lightly with the foot
Continue filling and treading more firmly but do not firm too hard in wet conditions
Fill all parts of the hole and tread firmly with the heel of the foot, leaving the firm soil slightly proud of the surrounding ground
Secure tree to stake if provided
If dry, water well
Rake and tidy up and apply mulch (mulching helps retain moisture, controls temperature and prevents weed growth. Use bark or composted woody material, a mulch mat or cut up squares of carpet).
Small transplants up to 1 m high can be planted without staking, but larger trees - particularly on windy sites or where there is a risk of vandalism or vehicle damage - should have stakes which should be driven firmly into the base of the hole BEFORE planting. Tying the tree to the stake helps hold the tree steady until the roots can provide firm anchorage: it also helps to avoid the tree being rocked by the wind as it can cause a cavity around its base and let air penetrate and dry out the roots. Research indicates that a short stake reaching about a third of the way up the stem, with a single tie, is preferable. Plant the tree close to the stake and fill and firm as described under ‘Planting'. Ensure that the space between the stake and the tree is well firmed. Put the stake on the side of the tree from which the prevailing wind blows, so that it does not blow the tree onto the stake, and secure the tree with a single tie.
There is often some risk of damage to newly planted trees. This can be caused by either domestic, wild animals or machines. Where this is likely, a suitable guard or a stout fence should be erected. Proprietary guards are available. If you plant groups of trees, fence around the planted area. Ensure that guards are large enough if larger animals like horses or deer are present.
All trees benefit from a good water supply in their first year after planting. Water should be applied slowly and allowed to sink into the soil. If the weather is very dry they will need to be given extra water, if very wet then don't water. Weeds and grass compete fiercely with newly planted trees for moisture and nutrients, so keep the ground around the base of the tree bare for at least three years to provide good growing conditions. Pull up all grass and weeds by hand, and top up mulch if necessary. Weed-killers can damage trees if used carelessly, and cannot be used outside your own land without a certificate. Check the tree's health at regular intervals.
For more information, see The Tree Council publications Trees in Your Ground and information leaflet Tree Planting - Planning and Practice.