Reasons for Pruning: To maintain healthy growth (health pruning); To establish and maintain a shape (formative pruning); To promote flowering growth, foliage, stems for colour; To control size?
Types of Pruning (Shrubs), Four Main Methods: Stooling (for growth) spring; Renewal (to maintain flowering) after flowering; Formative; And health pruning.
When to Prune: Deciduous trees and large shrubs: Deciduous trees (ones that lose their leaves in winter) are usually pruned in autumn and winter. In some cases, for example with Magnolias and Walnuts, pruning is best done in late summer, as healing is quicker; Trees such as Prunus sp, which are prone to silver leaf disease are best pruned from April to July when the disease spores are not on the wind, and the tree sap is rising rather than falling (which pushes out infection rather than drawing it in); Some trees can bleed sap if pruned in late winter and early spring. Although seldom fatal, this is unsightly and can weaken the tree. Birches and Walnuts often bleed if pruned at the wrong time.
Evergreen trees & shrubs: Evergreens seldom need pruning, although dead and diseased branches can be removed in late summer.
Pruning at planting time: Prune damaged, diseased branches and roots and formative pruning.
How to Prune Trees: Prior to undertaking any work, it is essential to ascertain if a Tree Preservation Order (TPO) is in place or if the tree is in a Conservation Area; If either is the case, seek permission from your local council before beginning work; Potentially dangerous limbs can, in theory, be removed without permission but the penalties for breaching the legislations, inadvertently or not, can be severe; Safety is of prime importance when working with trees, so make an honest appraisal of your capabilities, assess the area in which any branches may fall and erect warning signs or barricades if necessary before beginning; If in any doubt engage a professionally qualified tree surgeon or arboriculturist; Take a step back and decide what needs to be done to produce a balanced, attractive tree; Work with the natural habit of the tree to shorten or remove branches; Going against the tree’s natural habit produces ungainly trees that lack grace; Always start by removing damaged, diseased branches.
How to Remove Branches, Limbs and Roots: Wear protective gloves and, if necessary, eye and head protection; When cutting a stem, cut just above a healthy bud, pair of buds or side shoot. Where possible, cut to an outward facing bud or branch to avoid congestion and rubbing of branches; Make your cut 0.5cm (¼in) above the bud. Beware of cutting too close, as this can induce death of the bud. Beware of cutting too far from the bud, as this can result in dieback of the stub and entry of rots and other infections; When removing larger limbs, make an undercut first about 20-30cm (8-12in) from the trunk, and follow this with an overcut. This will prevent the bark tearing, leaving a clean stub when the branch is severed; Then remove the stub, first making a small undercut just outside the branch collar (the slight swelling where the branch joins the trunk), followed by an overcut to meet the undercut, angling the cut away from the trunk to produce a slope that sheds rain; Avoid cutting flush to the trunk as the collar is the tree’s natural protective zone where healing takes place; There is no need to use wound paints, as they are not thought to contribute to healing or prevent disease. The exception is Plums and Cherries (Prunus sp), where wound paint may be used to exclude silver leaf disease spores.