Pruning Basics

Most of us have a basic understanding of what pruning is, but few of us know how to do it correctly. It's not simply shaping the plant to give you what you think is the best look; it's actually for helping to maintain the health of your shrubs and trees (which, coincidentally, adds to the aesthetics). Pruning correctly also stimulates new, fresh growth and the production of buds -- keeping your shrub looking new and young for many years.

Before you go shearing your shrubs into an unrecognizable box, get in tune with your plant and figure out a few things about it before you've actually damaged it.

What You'll Need to Know: 

1. Does your shrub bloom on previous or current year's growth? This refers to when your shrub sets its buds. A general (and by general, I mean most of the time, not all of the time) rule of thumb is that summer-flowering shrubs bloom on current year's growth and spring-flowering shrubs on previous year's growth
2. How thick are the branches I'll be cutting and which tools will I need?
3. Is any of it dead, diseased or injured?
4. Should I really prune it back to a different height or width or should it be moved to an area where it can grow as it should?

1.
If you cut a spring-flowering shrub back in the late winter or early spring, you'll be cutting off all of the buds the shrub or tree has developed over the summer, fall and winter. This means you'll effectively make sure your shrub or tree doesn't have near the amount of flowers it's supposed to -- if any. Spring-flowering shrubs include lilacs, forsythia, weigela, viburnum, quince and beautybush, among many others.

Summer-flowering shrubs including rose-of-Sharon, philadelphus (mockorange) and butterfly bushes need pruning in late winter or early spring. These shrubs set their buds in the spring time, getting ready for their showy blooms in summer.

Some exceptions to this rule include many hydrangeas, which bloom on both old and new growth.

For shrubs that don't flower and are grown for their foliage, prune in late winter or early spring.

2.
The thickness of the branches determines which tool you'll need for the job. In general, hand shears (scissor-style, not blade-and-anvil style) cut branches up to about 3/4-inch in diameter; lopping shears (loppers) cut branches up to 1 1/2-inches in diameter; pruning saws are for branches up to 4-inches in diameter; and a chainsaw is for thick, larger branches.

3.
While there are certain times of the year you should prune, you'll want to cut out any dead, diseased or otherwise injured branches. Your shrub or tree is using precious energy to keep feeding these branches, energy it could use elsewhere.

4.
While you can prune to shape, you should never try to keep a large shrub in a small space. There are so many different cultivars of plants these days that you could probably replace that large, overgrown shrub with a smaller one that looks almost identical.


Before you begin pruning, you'll also need to know basic techniques. Don't blindly cut the branch anywhere you see fit, this could kill parts of branches. When pruning branches and twigs, always cut back to a side or main branch or about 1/4-inch above a bud that is facing outwards to promote growth in the right direction.

When you're cutting large branches, like those that come off the main trunk, you'll want to cut to the branch collar. The branch collar is particularly noticeable on trees where they're at eye-level. The branch collar is a swollen area that connects the branch to the trunk. Don't cut and leave a knob, and don't cut within the branch collar. Leaving an open wound on the branch collar can allow access for diseases and pests.

Again, these are just the basics; this isn't your only go-to guide for pruning ... yet ...