Dormant Pruning of Fruit Trees
Published in the Davis Enterprise January 25, 2001
Winter is pruning time!
Deciduous fruit trees, vines, and roses are all pruned now.
If you're going to do this yourself, you'll need the following tools:
- hand-held pruners, loppers, and a folding saw for smaller pruning work;
- a bow saw and/or chain saw for cutting large limbs;
- a pole saw and pole loppers for working higher up in trees (and consider some eye protection for this type of work),
- and a pair of nitrile-coated gloves for pruning roses.
Always use sharp tools. Locally, you can get them sharpened at JB's Power Equipment or Ganesh Fixit, both on Olive Drive.
We don't recommend the use of any "tree seal" compounds, such as the black tar-like compounds that used to be painted on pruning wounds. Researchers have found that they seal in moisture, like a bandaid left on too long.
Pruning of shade trees should be left to professionals, as improper pruning can make the tree prone to pest infestations, or lead to branch structures that are unsafe. Look for a certified arborist, and make sure they are licensed and insured.
Most of the fruit tree pruning and training recommendations in older books are geared to ease of orchard operations: spacing is based on tractor width, and training is intended to keep the trees up and out of the way for spray rigs. Homeowners generally want trees that can be pruned and harvested from the ground or from a short ladder.
The recommendations here are for deciduous trees. Citrus trees are evergreen subtropicals, so they are best pruned when there is no risk of frost damage (older, established trees are less vulnerable). They are pruned only for size control and aesthetics.
You can get lots of varieties of fruit over a long season (literally from May to November) by buying trees on rootstocks that will make them grow more slowly, planting them as close together as possible, training them with low branch structure, and even pruning some in the summer for size control.
In our family orchard many of our trees are 6' apart! You can even plant several trees together in a large hole, as long as you are willing to prune them to keep them small. Remember, you are in control of the ultimate shape of the tree!
Commercial growers and homeowners have differing goals in pruning. They prune to maximize fruit production. We prune to improve the structure of the tree, to control the size of the tree for easier harvest, and to reduce fruit production of larger-fruited types.
Reduce fruit production? Yes! A single peach, nectarine, or plum tree can produce hundreds to thousands of fruit. Drive by peach orchards as the fruit is maturing, and you will see a small fortune worth of 2 x 4's propping up branches to prevent them from breaking. Remember that most of these types of fruit ripen in just a period of a few days. How many fresh peaches can you eat or process in a week? Better to have a hundred fruit off this tree this week, then a hundred off that tree next week, than a thousand fruit all at once!
Major structural pruning...
...is done when the tree is dormant, anytime between December and the end of February. This is when we remove diseased or dead branches and crossing and rubbing branches; do any major cuts that are going to reduce the height of the tree, and remove a certain amount of potential fruiting wood on heavy-bearing trees. Winter is when we train young trees: select the well-positioned branches that are going to be the permanent branches when the tree is mature and prune out the center of the tree if we want a more open habit.
... is a relatively new technique used strictly for size control. This requires far less precision than dormant pruning, as you are simply heading back new growth (literally shearing like a hedge if you like) to keep the tree within picking range. In effect, you are intentionally stunting the tree. For more information on summer pruning, visit the web site of Dave Wilson Nursery at www.davewilson.com
Keep in mind the principles:
better structure, smaller size, less fruit on large-fruited types. It's also important to know where on the tree the fruit is produced, as this affects how severely we prune.
Severe pruning required:
Peaches, nectarines, plums, pluots.
The main goal is to reduce fruit production. All of these produce medium to large fruit all along last year's growth. On peaches and nectarines, last year's growth is conveniently red, compared to the grey of older wood. Left unpruned, these trees will set such heavy crops that the branches will collapse. Remove the central portion of the tree when they are young to keep the branches low. Thin out about half of what grew last year, and cut back the remainder of last year's growth by 50%!
Moderate pruning required:
Apricots, apples, pears, and Asian pears.
The main goal is size control. These fruit on short "spurs" which grow on 3 - 4 year old branches and persist, continuing to fruit, for many years. The trees are less likely to collapse from heavy fruit production, as the fruit is attached to older, thicker wood, but they may produce far more fruit than you want. Thin these trees by about 25%. Apples and pears (both European and Asian) produce vigorous, upright branches that should be pruned out. Cut these to a point where another branch already is growing.
Light or no pruning required:
Cherries, persimmons, figs, pomegranates, jujubes, quince, nut, and citrus trees.
... grow very upright, so early training for size control can be done to keep the fruit in picking range. They fruit on spurs, and we aren't concerned about the size of the fruit, so the major pruning we do to other stone fruits isn't necessary. It's important to know that cherries heal very slowly from large pruning wounds, so it's not a good idea to try to significantly reduce the size of a large, established tree.
Note: pie cherries have a graceful, spreading habit and only need light thinning.
Persimmons and figs...
... will get large and produce great quantities of fruit. Persimmons have very strong wood and can hold large crops without breakage, and they are very ornamental trees, so we generally prune lightly if at all. Figs are unique: they produce a crop in spring on old wood, and a crop (sometimes two crops) in summer on new wood. How many figs do you want? You can prune very severely for size control and still get plenty of fruit, or you can allow them to grow into large, attractive, tropical-looking trees and get even more fruit.
Pomegranates, jujubes, and quince...
... are large shrubs that don't need to be pruned at all, but they can be trained into small, multi-trunk trees, or sheared as a hedge, or topped for size control if you like. You'll still get more fruit than you can use!
Nut trees are very easy.
Since we harvest the nuts off the ground, we aren't worried about size control; fruit size is not an issue, and the crops aren't heavy enough to cause branches to break, so just thin them lightly and allow them to grow into large, graceful trees. Pecans in particular need careful training to prevent narrow branch angles and limb breakage.
Proper pruning enhances trees; improper pruning endangers them.
If you remember the basic principles of pruning: good structure, size control, and regulating fruit production, you can get many years of healthy, tree-ripened home-grown fruit from your yard!
For information on rose pruning, click here.