As we’re preparing our yards and gardens for the season, it’s time to consider when and how to prune trees and shrubs. A good pruning is often in order to improve the health, productivity and appearance of these backbones of the landscape.

The key to proper pruning is knowing the best time to prune and how much to cut, and since every plant type is different. It’s important to understand the goal before you step in with sharp instruments in hand.

Clean and prepare your tools

Before beginning any pruning project, have your equipment in good shape. You don’t want to stop mid-way through your efforts, or struggle with tools that won’t cut cleanly. There’s nothing worse than struggling with a branch, or leaving a ragged edge. That not only looks unsightly, but leaves the tree (or shrub) vulnerable to disease. Use a rasp to sharpen pruners, both the hand clippers and loppers. Depending on the size of the branches to be cut, have  a small saw ready to make quick work of the larger limbs.

Another consideration for your tools is cleanliness, and this is particularly so when it comes to fruit trees. Fire blight and other issues can ruin an otherwise healthy tree. Before you begin to use your tools, dip them in a bleach solution (thoroughly drying them with a towel afterwards). Alternatively, clean them with antibacterial wipes. If fire blight, a bacterial disease, is an issue in your area, wipe the blades after every cut throughout the process of trimming fruit trees. Thankfully, this isn’t typically necessary with ornamental shrubs because they are not as prone to these various disease issues.

Pruning fruit trees

Fruit trees are best pruned while they’re still dormant, often beginning as early as February, and continuing to April, depending on your location. The point is to remove extraneous twigs and branches so the energy of the tree is focused on fruit production.

Before you touch the tree, step back and take a look at it, as you’ll want to consider form as well as function. Look for anything that appears out of place. Remove any dead or damaged branches. Cut-out any branches that cross over one another, grow downwards, or that are just plain in the way. The rule is: if a limb sticks out, and it’s bothersome, cut it off. You can also remove branches that are too long since these gangly appendages will not produce well. Trim them at an angle at the end of a bud. You’ll also want to snip out any water sprouts, suckers, or branches that grow straight up as they typically are not productive. Another rule: don’t remove more than 30% of the tree.

Once this is accomplished, it’s time to shape the tree to a productive form. There are two popular pruning systems for stone fruits (that is, fruits with a pit). One method is called the open-center system. The natural shape of many fruit trees resembles a vase. In this situation, the center is cleared to allow light to reach all of the branches.

Apple Tree Pruned to Open-Center Style – Photo by Amy Grisak

Another pruning method is known as the central-leader system. It allows the tree to grow in a more natural shape while providing plenty of strong branches for heavy production. When training a fruit tree in central-leader fashion, keep in mind you are creating whorls with lateral branches stepping up the main trunk. A bit confused? Picture a spiral staircase. The first branch starts at approximately 24 inches from the ground, with the next lateral branch roughly 6 to 8 inches above, and away, from the first one. Always keep in mind that you’ll want light to reach the lower branches. Continue this pattern the entire way up the tree to where you might end up with 4-8 branches.

Regardless of method, you can safely cut up to 30 percent of the tree overall. It’s perfectly acceptable to trim severely, but be sure to leave the flower buds. If cut, fruit production will be severely limited.

For larger trees that haven’t been pruned for a long time, it might take several years to bring them into shape. Remove any errant twigs or branches, including those that grow straight up and cross-over, just as suggested with young trees. Next, cut-out branches as necessary to work towards the desired form. This might mean removing only one or two large branches the first year. Your patience will be rewarded with a much healthier tree in the end.

Careful Pruning Results in Bumper Crops – Photo by Amy Grisak

When to prune lilacs and spring flowering shrubs

It might be tempting to trim spring flowering bushes before the season begins. But, by doing so, you will reduce, if not eliminate, this season’s blooms. Instead, wait until they bloom, then remove the spent flowers just below the flowerhead. Don’t forget to remove any errant twigs and branches. Doing it in spring gives the plant the rest of the year to grow new flower buds. By next season you will have a shapelier shrub and one loaded with blooms.

Lilacs, in particular, benefit from annual pruning to thwart their tendency to overgrow and become less productive. Cut out the shoots at the base of the shrubs every year. Lilacs are well known to send suckers everywhere, but they typically do not improve overall health or flower production. Also, remove any particularly old or misshapen branches. These might be in the center of the bush and could be challenging to reach, even with a small saw. However, opening up the center aids air circulation. This is also a good time to cut back any branches that are in the way of either a pathway or view. You can cut the branch as far back as needed. However, be aware no flowers will bloom on it for at least a season.

Summer shrub maintenance

Spring is the best time to shape summer blooming shrubs such as Spirea, because they bloom on the new growth. Remove any diseased or broken branches, then begin trimming Individual branches to fit your desired form. If the shrub is at an acceptable size where you really don’t want to grow larger, simply trim branches to the first set of leaf buds. That will encourage the formation of new blossoms.

Harsh cuts: rejuvenating pruning

There are some years when a gentle trim is not going to do the trick. Overgrown shrubs are not productive, or beautiful, and can only worsen as overgrowth promotes disease and damage. In this situation, first remove anything that is dead as close to the ground as possible. Then, cut the rest of the shrub to within 8-10 inches of the soil level. Of course, there will be no blooms after this type of pruning, but it will be well worth it in the long run.

Trimming evergreen shrubs

On occasion, evergreen shrubs need a trim to maintain their shape, and it should be done before the growth begins in the spring (except for pines, which benefit from trimming the new growth to maintain the shape). As with general pruning, remove any dead branches or those that are in the way of anything. From there, trim each of the branches to the desired height, preferably not taking off more than a few inches.

For pines, trim the new growth (called candles) when they’re a couple of inches long in order to keep the tree within its proper shape. Be aware that if you cut beyond the seasonal growth onto the old wood, you will simply have an unsightly branch end. It does not develop new growth at this time of the season.

Don’t Trim Pines Below the Candle – Photo by Amy Grisak

There are some evergreens, such as junipers, that often benefit from a rather severe pruning particularly since they have a tendency to die out in the center of the plant, or can grow well beyond their intended borders. Cut back branches up to a third of their length, along with completely removing any that are growing in the wrong direction.

Dead Branches Should Be Cut Out of Junipers – Photo by Amy Grisak

Yews are one of the rare exceptions in the world of evergreens that tolerate a severe pruning with barely slowing down their growth. If they are unwieldy, they can be cut to the base of the trunk, and will bounce back within a season or two.

When not to prune

For the most part, do not prune any deciduous trees or shrubs in late summer. By August they should begin shifting to prepare for the winter dormancy, yet a late season trimming encourages a flush of new growth, making the plant less vigorous and more vulnerable to damage. This is also true for evergreen shrubs, which also need to harden off and prepare for the winter season. Any new growth is far too tender to withstand cold conditions, and you’ll most likely end up having to prune out more dead areas the following spring.

A satisfying task

Pruning can be hard work, particularly if there are large branches to remove, but it is one of those tasks that feels good once it’s accomplished. It allows you to step back to assess your efforts, which usually results in a lovely looking feature that is far healthier in the long run.