Most plants are pruned in winter, when dormant, but there are exceptions. Cherry and plum trees, for example, are susceptible to silver leaf disease, and should therefore be pruned in summer when the risk of infection is reduced. Likewise, most spring-flowering shrubs should be pruned immediately after flowering.
Most professionals advise against pruning after late July, because new growth that develops will not be hardened off enough to withstand the cold months and may simply die back over winter.
Pruning during the growing season always stimulates new growth. During summer's heat, having to produce that ill-timed new flush of growth greatly stresses a tree. Pruning in the fall is even worse as it prevents the tree from going into a natural dormancy. The exception is heavily damaged, disease or dead wood.
Shrubs can be pruned any time they need it. It is better if they get pruned earlier rather than later. This will probably result in the loss of some flowering though. If the shrub is growing something that looks way out of line, prune it as you want.
Summer is an excellent time for restorative pruning. Summer pruning tasks may include removing dead, damaged or diseased branches. Many people think of pruning as a winter task, but there are a number of great reasons to prune your trees and shrubs in summer.
The 1/3 rule involves cutting about 1/3 of wood during any pruning activity. This kind of moderate pruning is like giving your shrubs a good balance – it thins them out a bit and encourages new growth.
These are the 3 Cs (crossing, competing and crowding) of pruning. On grafted trees you might see growth below the graft or in the ground, this is the rootstock trying to express itself as its own tree. These can be removed anytime as they rootstock growth will divert energy away from the grafted tree.
The first consideration for pruning the canopy of young trees is called the Five D's. These are branches that can and should be removed at transplanting, or at any time as the tree is maturing. The Five D's are any branches that are Dead, Dying, Damaged, Diseased and Deformed.
A proper pruning cut minimizes the damage done to the tree and allows it to heal quickly. An improper cut like a flush cut (cutting too close to the trunk) or a stub cut (cutting too far from the trunk) can cause irreversible damage to a tree.
Spring flowering trees should be pruned after flowers have dropped. To avoid the introduction of disease pathogens to oaks and elms, avoid pruning between April 15 and October 15. Prompt pruning of storm-damaged limbs and dead branches should be done to encourage wound closure and avoid potential hazards.
When making pruning decisions, keep in mind that you can safely remove up to one-third of the plant's growth at any one time. There may be times when you prune more, such as when you are rejuvenating an overgrown shrub, but generally speaking, the “one-third rule” is the best guideline to follow.
Dead wood can be removed anytime from any plant, but shrubs that bloom before the end of June should only get touch up pruning in May. More can be cut after the flowers finish if needed.
If you notice that your trees aren't growing as well as they should be or are losing foliage, it's possible that you've pruned them too much. Additionally, an increase in interior sprouting indicates over-pruning, which is when they grow sprouts internally rather than on the tips of limbs.
Don't prune too late in northern regions.
In areas with cold winters, avoid pruning after the middle of August. If you prune too late, you may stimulate new growth that would not have time to grow thick, protective bark before the killing frosts of winter.
The 1/3 rule for pruning shrubs refers to the practice of cutting about 1/3 of wood or a branch. This approach is applied to fully established shrubs and small trees. This is done at this stage since the established shrubs and plants are past their transplant shock.
Any experienced tree care worker can tell a bad pruning cut from a good one. Some bad pruning examples include: Stub Cuts: These cuts leave a branch stub that prevents the tree from sealing the wound to protect it from diseases. If you can hang something off the end of a branch, it's an incorrect pruning cut.
Generally, a deciduous tree's recovery can span from one to five years following pruning. The tree's size during pruning, the degree of damage from pruning, the tree's health before pruning, and the environmental conditions afterwards all contribute to the recovery period.
Tree pruning involves the removal of live branches, as well as dead, diseased, and damaged branches for the health of the tree, while tree trimming only involves the removal of branches that interfere in some way.
Start with the three 'Ds' – dead, damaged, and diseased. Next, look for branches that are rubbing, or those weakly attached.
ALWAYS prune back to or just above a growing point (branch or bud) or to the soil line. NEVER leave a stem or branch stub. NEVER top a tree to “rejuvenate” growth. Â This ruins the plant's natural shape and greatly increases its susceptibility to diseases, insect pests, and storm damage.
Do not prune deciduous shrubs in late summer. Pruning shrubs in August or early September may encourage a late flush of growth. This new growth may not harden sufficiently before the arrival of cold weather and be susceptible to winter injury.
As a general rule of thumb, plants that flower early in spring or flower on old wood (previous season's growth) should be pruned immediately after they flower. Plants that flower on new wood (current season's growth) can be pruned in late winter or early spring. Here is an overview of what to prune and when.
3) The 3 in 1-2-3 refers to 3-year-old wood that was cropped when 2 years old and sometimes 1 year old. Renew the 3-year-old wood by cutting it back hard (Figure 3). This way you will generate new laterals, and the cycle starts again (Figure 4).