How to Prune Plum Trees; The Complete Guide

Expert advice from the tree specialists at Frank P Matthews

Plum trees are a firm favourite in UK gardens, valued for their spring blossom and generous crops of juicy fruit. However, knowing when to prune plum trees and how to do it correctly is essential. Unlike apples and pears, plum trees and other stone fruit trees need a more careful approach to reduce the risk of disease and ensure long term health.

At Frank P Matthews, we have been growing fruit trees for generations, supplying gardens, orchards and landscapes across the UK. In this complete guide, we explain how to prune plum trees in the UK, the best time to prune and how to care for both young and mature trees.

Why pruning plum trees matters

Pruning helps plum trees maintain a strong structure, prevents branches breaking under the weight of a heavy crop and encourages better air circulation and light throughout the crown. Well pruned trees are more productive, easier to manage and less likely to suffer from disease.

Plum trees are particularly susceptible to silver leaf disease, which is why pruning methods and timing are so important. Correct pruning reduces risk while helping the tree bear fruit consistently.

When to prune plum trees in the UK

One of the most common questions we are asked is when to prune plum trees UK gardeners are growing. The answer is very different from other fruit trees.

Plum trees should be pruned during the growing season, typically from late June onwards. Summer pruning allows cuts to heal quickly and reduces the risk of infection.

As a general guide:

• Summer pruning from late June through to early autumn is ideal
• Mid summer is the safest and most effective time
• Winter pruning should be avoided wherever possible

This differs from apples and pears, which are usually pruned in winter. Plums, cherries and peaches should not be treated in the same way, as winter pruning significantly increases disease risk.

For more general advice, you may find our guide to pruning fruit trees useful.
Internal link: How to Prune Fruit Trees

Pruning young plum trees

Pruning young trees is about creating shape and structure rather than limiting growth. Newly planted trees, including bare root trees, need very little pruning in their first year.

If a planting cut is required, it should be done to establish a strong central stem and evenly spaced branch leaders. The aim is to develop a balanced framework that can support future crops.

In the first summer:

• Select three or four main branches spaced evenly around the trunk
• Remove weak shoots and any side shoots growing too low
• Encourage branches to grow outwards rather than inwards

Always cut to an outward facing bud to promote an open shape. Avoid heavy pruning in the first summer, as this can slow establishment and affect root growth.

How to prune established plum trees

Once established, plum trees benefit from regular light pruning rather than infrequent heavy cuts. Maintenance pruning helps control growth, manage fruit production and reduce strain on branches.

Start by removing:

• Dead branches
• Damaged branches
• Diseased branches
• Branches that cross or grow inwards

Removing diseased wood promptly is essential to avoid infection spreading. All cuts should be clean and tidy, close to the branch collar but without damaging the trunk or main stem.

Next, thin side branches where growth is too dense. This improves light levels and air circulation, which supports healthy fruiting and reduces disease risk.

As a rule, do not remove more than about a third of the tree in any one year. Removing too much growth at once can stress the tree and encourage excessive new shoots.

Summer pruning and fruit production

Summer pruning plays an important role in balancing growth and fruiting. Plum trees can be very vigorous, especially when growing in fertile soil or good light conditions.

Light pruning during summer helps:

• Control vigorous growth
• Reduce the risk of branches breaking
• Improve fruit size and quality

If a tree sets too much fruit, thinning can be beneficial. Removing some fruit reduces weight on branches and allows the remaining plums to develop properly, resulting in better quality fruit at harvest.

Restoring a neglected plum tree

A neglected plum tree often has overcrowded growth, crossing branches and a high risk of damage under the weight of fruit. Restoring it should be done gradually.

In the first summer, focus only on essential work. Remove dead, damaged or diseased branches and any growth growing inwards towards the centre of the tree.

Avoid removing about half or two thirds of the canopy in one go. This can shock the tree and increase the risk of silver leaf disease. Instead, spread pruning over two or three seasons.

In the following spring and second year, continue with careful thinning and shaping. Over time, regular pruning will restore balance and improve fruiting without compromising the tree’s health.

Avoiding silver leaf disease

Silver leaf disease is one of the main risks when pruning plum trees in the UK. It enters through pruning wounds, particularly during cool, damp conditions.

To reduce risk:

• Prune only during summer when growth is active
• Avoid pruning during wet weather
• Use clean, sharp tools
• Remove and destroy diseased branches

Good hygiene and correct timing are key to keeping plum trees healthy.

Tools and pruning technique

Using the right tools makes a significant difference. Secateurs are suitable for small shoots, while a pruning saw is needed for larger branches.

Always clean tools between trees and between cuts if disease is present. Make smooth cuts and avoid tearing the bark, as damaged tissue heals more slowly and increases infection risk.

Frequently asked questions

Can I prune plum trees in winter?
Winter pruning is not recommended due to the increased risk of silver leaf disease. Summer pruning is far safer.

How much should I prune each year?
Aim for light pruning, removing no more than about a third of growth annually.

Do plum trees need pruning every year?
Yes, regular pruning helps maintain structure, manage growth and improve fruit production.

Are plum trees pruned the same as apples and pears?
No. Apples and pears are usually pruned in winter, while plums should be pruned in summer.

Expert advice from Frank P Matthews

At Frank P Matthews, we grow and supply plum trees suited to UK gardens, orchards and landscapes. Understanding when to prune plum trees and how to prune plum trees UK conditions demand is essential for long term success.

With careful timing, light but regular pruning and attention to hygiene, plum trees can remain productive and healthy for decades. If you are planting new trees or caring for existing ones, our expert advice and wide range of fruit trees can help you achieve the best possible results.