Pruning Fruit Trees

It’s never to early to start thinking about pruning, especially fruit trees. Mature, fruit yielding trees require regular pruning to stay healthy, to maintain their size and shape, and to open their branches to sunlight. Proper pruning will ensure large, well-developed fruits when harvest time arrives. Last season I saw more diseases on fruit trees than I have seen in many years – powdery mildew, apple scab, shothole fungus, and fireblight, to name a few. Unfortunately, many of these same problems will return this year. A well timed
pruning and an application of a dormant oil and fungicide combination will help solve many of these problems before they start.

A late frost damaged many crops around the valley last May and fruit production decreased dramatically. Expect to see fruit production up this coming year because of the damage last season, and so we’ll probably see problems with over-production, thinning concerns, and trees splitting because of excessive weight on the branches. This is one of those years where some extra thought and planning ahead of time can save some damage and increase your harvest this fall. Many of these problems should be addressed now, during pruning season.

The best time to prune a fruit tree is from dormancy until its blossoms open in the spring. In Cache Valley, this usually occurs from late February to early April. I recommend that you do your pruning sooner than later. Do it now when there isn’t fifty other things that need to be done outside, because as it warms up, you know that the list of things-to-do will only get bigger. I also believe that pruning while the tree is completely dormant does less damage and wastes less of the tree’s energy on growth that is pruned and discarded. So, start pruning. And believe me, now beats trying to get it all done in May.

First, determine whether you can tackle this job, or should you call someone else – namely a professional. How many trees do you have? How much money are you willing to spend for someone else to do it? How much time do you have? If you have more than four or five, good-sized, fruit trees, don’t have a lot of time, and don’t feel very confident about doing it yourself, you might want to consider hiring an arborist. There are some very good arborists in Cache Valley, but they are extremely busy. Call early and set up an appointment or else you might end up doing it yourself anyway. Next, make sure you have the proper equipment. Sharp, well-maintained, good-quality tools will make your job much easier. Also, you need the right tools for the job. Without a hand pruner, a lopper, and a saw, you might as well forget it. For larger trees, a pole pruner and a chain saw also come in handy. When you don’t have the right tool for the job, human nature prompts us to improvise with what we have. I think we all have done dumb things with tools in the past, but sometimes it is because we didn’t have the right tool in the first place so we tried to make do with what we had. Don’t make that mistake when pruning – those lopper handles can get expensive.

How to prune depends very much on the type of tree. Peaches flower on year-old wood, and therefore benefit more from a severe pruning. Apples and pears flower on old wood and require a more selective pruning. Some trees, such as plums and cherries, flower on both year-old and older wood. Keeping in mind the different needs of your trees, you can adapt these general instructions to all your fruits as well as to deciduous
trees and shrubs.

Always begin by cutting back all dead, broken, or diseased branches to the trunk or to healthy buds. Dead wood appears shriveled and lifeless, while buds on healthy wood swell with life during the dormant season. Also, check for evidence of disease, such as dark lesions or the black specks of fungal spores and cut off the infected branches 6 inches back from the diseased area. This is also a good time to remove any branches that cross over or crowd others.

Remove less productive wood–water sprouts or vigorous vertical branches, branches that droop downward, and twiggy branches growing from the underside of limbs. Remove water sprouts at their bases. Drooping branches, if still young, should be shortened to stimulate growth from buds just below the cuts. If older, cut them back to side branches growing in horizontal positions. Finally, remove weak and unproductive branches that grow from under the limbs. When in doubt, do a little research before pruning just to make sure you know what to look for.

When you finish pruning, don’t forget to apply a dormant spray. Often forgotten, the dormant spray is one of the most important steps a fruit grower can take. A straight dormant oil spray works fine for insects. It coats the tree with a thin layer of oil that suffocates insects and insect eggs that may have wintered over from last year. It will certainly help if you had a heavy infestation of aphids. If you had disease problems last year, such as powdery mildew, fruit scab, or leaf curl, use a dormant oil-fungicide combination to control any diseases left over from last year. This is essential if you had problems with scab, leaf curl, shothole fungus, or fire blight, plus it will help prevent other diseases as well. Don’t miss this spray! It won’t guarantee that your trees will be bug and disease free for the whole year, but it will help considerably. You’ll be surprised what a difference it can make.

Remember that there are many resources available to help you achieve success in your pruning endeavors. Local garden centers and nurseries have experienced professionals that can answer your pruning questions and demonstrate proper techniques. The USU Extension service provides invaluable information for home gardeners on a variety of topics and can help you with your pruning questions as well. Finally, many professional arborists are willing to share their knowledge and experience when you want to do the job yourself. They too like to see a pruning job well done.

How to prune depends very much on the type of tree. Peaches flower on year-old wood, and therefore benefit more from a severe pruning. Apples and pears flower on old wood and require a more selective pruning. Some trees, such as plums and cherries, flower on both year-old and older wood. Keeping in mind the different needs of your trees, you can adapt these general instructions to all your fruits as well as to deciduous trees and shrubs.

Always begin by cutting back all dead, broken, or diseased branches to the trunk or to healthy buds. Dead wood appears shriveled and lifeless, while buds on healthy wood swell with life during the dormant season. Also, check for evidence of disease, such as dark lesions or the black specks of fungal spores and cut off the infected branches 6 inches back from the diseased area. This is also a good time to remove any branches that cross over or crowd others.

Remove less productive wood–water sprouts or vigorous vertical branches, branches that droop downward, and twiggy branches growing from the underside of limbs. Remove water sprouts at their bases. Drooping branches, if still young, should be shortened to stimulate growth from buds just below the cuts. If older, cut them back to side branches growing in horizontal positions. Finally, remove weak and unproductive branches that grow from under the limbs. When in doubt, do a little research before pruning just to make sure you know what to look for.

When you finish pruning, don’t forget to apply a dormant spray. Often forgotten, the dormant spray is one of the most important steps a fruit grower can take. A straight dormant oil spray works fine for insects. It coats the tree with a thin layer of oil that suffocates insects and insect eggs that may have wintered over from last year. It will certainly help if you had a heavy infestation of aphids. If you had disease problems last year, such as powdery mildew, fruit scab, or leaf curl, use a dormant oil-fungicide combination to control any diseases left over from last year. This is essential if you had problems with scab, leaf curl, shothole fungus, or fire blight, plus it will help prevent other diseases as well. Don’t miss this spray! It won’t guarantee that your trees will be bug and disease free for the whole year, but it will help considerably. You’ll be surprised what a difference it can make.