I’m a fan of plums, but I’m not a big fan of working outdoors at the peak of summer under a neck burning sun. Therefore, I’m happy with the time of year that pruning plum trees is most beneficial for the tree’s health.
Late winter to very early spring is usually the best time to prune plum trees. Some reasons for pruning at this time include the fact that the tree will be able to heal from cut wounds quickly, and you will more clearly see what parts of the tree are dead and need removing.
Why pruning at the end of winter or early spring is the sweet-spot
This time of year can be the best time to prune your plum tree, because you get to see what branches are dead or healthy. Your tree is about to to use a lot of energy for spring growth. By cutting away the branches that aren’t healthy or desirable, all the energy will flow into the healthier branches, meaning that overall you have a better tree.
The above also explains why pruning during autumn is such a bad idea. In autumn, instead of the tree using energy, the tree well actually withhold releasing energy. This means the tree will find it difficult to heal it’s wounds that it may receive from cutting and trimming.
Late January to very early March could be the best time for you. In saying that, every year’s climate is different and different areas of the world have differing weather due to geography. Some good rules to go by if you don’t want to follow a simplistic month calendar guide, is by looking at the the last time there has been a heavy frost in your location. If its been a fortnight since the last extreme frost then it may be a good time to start pruning. Additionally, keep an eye on the buds. Try to begin pruning before bud swelling happens. Remember not to prune too early. Pruning too early during the height of winter may lead to increase sucker growth from the rootstock that could decrease the fruitfulness of your tree.
Pros and cons of pruning after spring arrives
Pruning a plum tree in spring does bring some benefits. Firstly, the weather is often milder than during the sweet spot of pruning. It might be during a time where there is little risk of snow or early morning frost, meaning that you won’t be freezing when trying to remove some troublesome branches from you’re adored plum tree. Also, it’s well before the potential scorching heat of summer in many places.
Another benefit of pruning in spring is that you now can more clearly see which branches are healthiest and most productive.
Moving onto the cons, when you prune in spring the tree has already used up a good bit of its energy on growing its branches. This means you’re not getting the the highest productive efficiency from your tree regarding healthy and fruitful branch growth. This underlines the importance of pruning a little bit earlier. For the vast majority of plum tree growers they want their trees to be as healthy and productive as possible . Avoiding pruning later in spring may just help you achieve this result.
Some of the benefits of pruning during the summer
One of the big benefits of pruning in summer is that you can target new shoots that have grown on the tree. By removing these shoots you can ensure that the other older branches that are healthy receive more sunlight. The extraction of these newbies also improve the circulation of air around other branches of the tree. This circulation of air may help in the fight against unwanted disease and pests making their presence felt on the tree.
The tree also doesn’t have as much energy as spring, therefore by removing unneeded branches the energy is thus more focused on the established and productive branches. The energy can hence be more effectively used.
The right tools for pruning during the sweet-spot
When you have decided on what branches are the target on your plum tree then you must consider what specific tool to use. The most important tool of all tools to use when pruning a tree is of course a pruner . For small thin branches you should use a pruner shears or hand pruners. Of course, any tool with blades can become blunt. Therefore, always make sure they are appropriately sharpened or you have a fresh pair when your old one doesn’t do the job.
For bigger branches it is recommended that you use a hand saw. Sine these can be a bit more dangerous then pruners, always use with care.
What exactly to prune off your plum tree
If you have planted a new plum tree whip or you have just transplanted a very young tree, then don’t be afraid to cut off up to a third of it. This will focus the energy of the tree on fewer branches and on the roots. This process overall gives you a better chance of having a tree that will go on to be stronger and healthier in the coming years.
The process of pruning a plum tree is to give you the best chance for it to be as healthy and productive as possible. Therefore, you should prune away any unwanted branch that comes in contact with or blocks the sunlight of a branch that you would like to see remain. Additionally, you should remove branches that are growing inwards towards the tree as these branches might undermine optimal air flow around your plum tree. These actions will all increase the chances of you having a more productive tree with better fruit.
What training system should you use?
You need to be mindful however of not cutting any branch that may lead to an outcome that you are not satisfied with. For example, if you were to remove the center branches or leader branches of the tree, then you might increase the likelihood of the remaining branches receiving more sunlight and good air circulation. The training system that incorporates this is the open vase training system.
With an open vase training system for a plum tree, over the years the remaining branches might grow wider than you have anticipated as energy is focused away from the now non-existence central branches and toward the side branches. This could cause issues if you are growing in a small space, say a crowded backyard for example.
For plum trees a central leader training system is often recommended. The tree usually has natural leader branches, a growth pattern that include long, upright branches. You should hence consider keeping the side branches in check if you want optimal fruit growth. This system uses this strategy and results in a cone or pyramid shaped tree.
Another training system that you could use for plum trees is the espalier training system. This works well if you have very limited space or would like to cover up a plain wall or empty space around the outside of the house. The tree should be planted about half a foot from the wall or fence. This promotes the circulation of air. Horizontal wires should then be placed along supports like bamboo sticks, either side of the tree. You will then bend the branches and connect them to the wire. This will encourage the branches to grow out in the espalier fashion.
Don’t overlook suckers
Of all things that need to be pruned and can be often overlooked is the suckers sprouting up from the roots at the base of the tree. These suckers may be from the attached rootstock to your tree and possibly won’t produce any plums or fruit. In fact, all they will probably do is lower the level of productivity that your desired tree can achieve. Never hesitate from removing them.