Both trees and shrubs can benefit from pruning, both to control their size, prevent disease or pests, or to repair weather damage. Deciduous trees and summer and fall flowering shrubs can most safely be pruned while they are dormant in winter.
General Pruning Guidelines
These guidelines apply to all pruning, not just winter pruning.
- Always remove died or damaged branches.
- Remove any branches growing to the inside of the plant; improved air flow in the interior of the plant can prevent disease.
- Remove crossing branches to prevent damaged bark that can be susceptible to disease.
- Avoid pruning in April (when leaves are opening) and October (when leaves are falling).
- Never, ever, control the size of a tree by cutting off the top. Topped trees are highly susceptible to disease, pests, and other problems.
- Do not seal pruning cuts with pruning paint or a wound dressing. The wound will heal itself.
- Use sharp secateurs or loppers to avoid tearing the bark.
- Clean pruning tools with chlorine wipes after each cut to avoid spreading disease.
For a free regional pruning guide and articles on pruning, visit Plant Amnesty, a non-profit organization that advocates for conservation of urban trees. The Virginia Tech Cooperative Extension Web site offers a table on when common deciduous trees and common evergreen trees should be pruned.
Use the Right Pruning Tools
Start any pruning with a sharp tool. Dull tools can tear the bark or fail to cut all the way through. Have several types of pruning tools ready, since you will need different types depending on the size of the branch or its location on the tree or shrub.
The most effective pruning tools are bypass pruners, sometimes known as secateurs, bypass loppers (longer than pruners to use for higher branches or thicker branches), and a pruning saw.
Carry either a bucket with a weak chlorine or water solution into which to dip the pruning tool after each cut, or chlorine bleach wipes to use to wipe the blades after each cut. This prevents the spread of disease.
Make the Right Pruning Cuts
More important than when you prune a tree or shrub is how you make each pruning cut.
Where you cut a branch or stem affects how the plant responds with new growth. To make sure new growth occurs where you want it to, always make your cut as close to the parent branch.
In Image 1 below, the pruner just whacked the branch wherever they felt like. As a result, the plant sent out new shots all over the top of the parent branch. This is called a "non-selective heading cut."
A proper pruning cut is shown in Image 2. This thinning cut, made in the notch between the parent and the unwanted branch, results in new growth only at the tip of the parent branch.
Once you finish pruning dormant trees and shrubs, you can carry out any dormant spraying needed to control the return of last seasons pests and diseases.
Mary Deaton - I have two passions in life - gardening and usable design. Gardening consumes my time from Spring to Fall. Until recently, I worked at ...
