A few years ago, some of you helped me edit a tree planting guide which became a pretty useful tool. Today I was trying to respond to someone's inquiry about pruning fruit trees (or any tree for that matter) at time of planting. I realized it might be worth writing a little about so I could save my response for future conversations. Can you look over the text below and see if you see anything I left out, grammar mistakes, etc. I know it doesn't cover HOW to prune, but I don't think I will include that (it can be covered separately). Let me know what you would change:

1. Dead, diseased, rubbing, and heavily damaged (split, denuded, etc) limbs should be removed immediately at any time of year, including at time of planting.

2. Trees should be trained/pruned for proper form early in their life. Correcting structural issues can become much more difficult as the tree gets larger.

3. Significant pruning of healthy branches (that would result in lots of foliage loss, reduction in the number of apical buds (shoot tips), and reduction of considerable amounts of energy-storing xylem) should be avoided at time of planting.

It’s still very common, despite research showing disadvantages, to see recommendations by nurseries, and even some educational resources, to prune trees and shrubs at the time of planting. There are multiple reasons for this, and I will cover the most common ones.

One reason is that it used to be thought that balancing the ratio of top growth (shoots/foliage) with root mass was important to the health of the tree. This has long been debunked. Properly dug/prepared trees can survive and actually become established much more quickly if top growth is left. The growth of tree roots is triggered/driven mostly by the hormone indole-3-acetic acid (IAA). IAA is produced in apical buds (shoot tips), so, if we cut back a lot of the top growth of a newly planted tree, we discourage the tree from further developing its root system by reducing production of IAA. Pruning also reduces the tree’s ability to produce energy, needed for root growth, by reducing the amount of foliage which is where photosynthesis produces energy. Stored energy is also decreased because of the loss of xylem, where energy is stored. All of these factors inhibit the tree’s ability to become established quickly and present increased opportunity for poor health and pest/disease issues.

A second reason pruning at the time of planting may be recommended is to improve the structure of the tree. This is especially the case for fruit trees where lower scaffold branching may be desired. It is indeed important to address structural issues as early as possible. Correcting them can become more difficult as the tree gets larger. However, there’s nothing magical about making the necessary changes during the planting process. This is often one of, if not THE, most stressful times during the life of the tree. Waiting until the tree becomes better established before major pruning can allow the tree to overcome this difficult time more effectively, and the necessary training/pruning can be carried out after that hurdle is overcome.

A third reason for the recommendation to prune at the time of planting is because some writers may be trying to take into account that many people may plant-and-forget the tree. This is a valid concern and may fit a majority of cases, but I’m not convinced it is a reason to present the option as a best practice. The ideal time to prune most ESTABLISHED trees, in our part of the world, is late winter or very early spring, after the coldest parts of winter are over but before the spring flush of growth begins. If a young tree is planted at the optimal time (mid to late fall, just after or around the time of leaf drop), it is likely to be established enough for structural pruning by that spring. A large percentage of root growth occurs, in most types of trees, during late fall and early winter after leaf drop. So, the tree can be ready for pruning relatively quickly. If the tree is planted in the spring, when many nurseries offer their trees for sale, a better time to prune would be late winter/very early spring of the following year, once the tree has developed a decent root structure and is able to vigorously cover over its wounds and begin growing correctly. In either case, the pruning will have been done in plenty of time to avoid lots of extra effort.

One last thing I want to cover is how some sources, especially when talking about fruit trees, may give you a certain height to which you should head back your young tree. The suggestion is made to encourage scaffolding branch development. Different types of fruit trees tend to do better with one or more specific structure styles. Different styles will affect things like ease of maintenance, ease of harvesting, fruit production, health of the tree, etc., etc. Examples of these styles are “central leader”, “modified central leader”, “open center”, “espalier”, and “tall spindle”. There is no one-size-fits-all approach to structure style. You should absolutely give some thought as to which style your tree should follow before any structural pruning! Also, if you plan to mow around your tree, think about how high your lowest scaffold branch should be to avoid problems.