Whether you’re an avid gardener or a brand new homeowner with no gardening experience at all, the fact is, at some point in your life you’re going to have to do some pruning in your yard. Pruning is a fact of life, and because shrubs are among the most common landscape plants in our yards, you can pretty much bet that you’re going to be pruning a shrub or two in your time.

Contrary to some urban myths being propagated out there, pruning is actually quite simple and straightforward, and is certainly nothing to fear. Like most aspects of our yards and gardens, the secret to a successful pruning lies in knowledge, both of the appropriate techniques to achieve the intended outcome, and of the plants that are about to be pruned.

So before you pick up your pruning shears and head out into the yard for a little chop-chop, be sure to read through this Info Sheet and know what you’re doing. Even if you’re a seasoned veteran of the manicured shrub border, it might not hurt to refresh your knowledge and be sure you’re on the right track!

First and foremost, be sure to have the right tools on hand. Sharp pruning shears are a must for every gardener and homeowner - the higher the quality, the easier it will be and the longer they will last. You can also have secateurs, lopping shears, pruning saws and other such tools, but the basic shears are essential. If you have a hedge, a set of power shears will make life much easier, but is not essential. Make sure to keep your shears sharp, and prep them for winter storage each fall with a light application of oil.

Before you start cutting away, be sure you are able to visualize just what you want the plant to look like after the carnage is over. If not, always step back and have a look before cutting - it’s always easier to see things more clearly from a distance. But don’t fret if you make the “wrong” cut. Most shrubs are very forgiving and will fill in an errant trimming in no time. Heaven only knows, I’ve chopped off a wrong branch here and there, and it’s never cost me a plant yet!

When pruning, you should always trim a branch back to just above one or more healthy leaf buds, no more than about half an inch above. Don’t leave stubs; these will invariably die and can become havens for insect pests and disease. Also note that some evergreens like pines and spruce only have terminal buds, and should be treated a little differently. These are best pruned as the new growth is vigorously developing in early summer; cut back a portion of the newer growth (often called "candles") to control their shape.

It is critically important to know when to prune your shrubs. Some of the techniques I describe below can only be performed at certain times of the year, and you are advised to follow the instructions faithfully. With other techniques, the shrubs can be pruned at almost any time, although there may be consequences. Specifically, there are two primary considerations when it comes to the right time to prune shrubs.

The first has to do with the time frame in which a particular shrub blooms. Obviously, if you’re undertaking a brutal rejuvenation pruning, you’re not going to be expecting much in the way of a flowering performance that year, or even for a year or two down the road. But for an annual trimming or pruning to shape, it becomes very important to know when a shrub blooms in order to ensure that it will still perform as intended that season.

The rules are actually quite simple. You should only prune summer-blooming shrubs in early spring, and prune spring-blooming shrubs immediately after they have bloomed. With spring bloomers, an early spring pruning will actually remove the flower buds and could severely inhibit any flowering performance, while waiting too late after they have bloomed could remove the newly formed flower buds for the next season. The key with summer bloomers is to not prune them after they have flowered, as this will probably be too late in the season for the vigorous new growth that will ensue to harden off to any safe degree.

Weigelas are an exception to the rule, and are best pruned after flowering

As a general rule, early spring bloomers form their flower buds the previous season and carry them through the winter. The flowering buds are therefore on the stems in early spring. Most late spring and summer-blooming shrubs tend to flower on new growth of the season, and are best pruned in early spring while still dormant. However, there’s a specific exception to this rule; shrubs which bloom on “new growth that emerges from wood of the previous season”. These include many of the viburnums (highbush cranberries) and weigelas; these are best treated as early spring bloomers and only pruned immediately after flowering.

One final note - there’s a morsel of advice that’s often proffered by our dear but oft ignorant friends in warmer climes which is thoroughly bad advice here in the North. Northerners, take note - you should never prune any shrub, for whatever reason, after about the end of July. Pruning stimulates vigorous new growth in most shrubs, and the last thing you want is tender new growth at the end of our short growing seasons when plants should be hardening off for the year. This is a recipe for disaster, even (especially) with hedges!

Pruning Methods for Shrubs