How to Prune Plum Trees

Plum trees should be pruned annually to maintain their healthy shape and encourage fruit production. The timing of pruning is crucial, as improper timing can lead to disease. Check out step 1 below to learn how to prune your plum tree for healthy growth and a beautiful shape.

Prune at the right time. You can prune during the summer or winter while the tree is dormant. Dormant pruning is done at the end of winter, after the leaves have fallen and no new buds have sprouted. This winter pruning encourages new growth in the spring and is less likely to damage the tree compared to summer pruning. Summer pruning typically slows down the growth of overly large trees and removes excessive new growth.

• Try to prune the tree at the end of winter before new buds form, as frost after pruning can damage the tree.
• Leave some branches to prune in the summer. Over-pruning in the winter can cause excessive growth and reduce fruit production.

Prune the seedlings after planting. Pruning the seedlings during their first dormant season is essential for healthy growth and shaping. Right after planting, cut the seedling down to about 75 cm, just above a bud.

• The new bud will sprout from the point you cut.
• Use sharp pruning shears for clean cuts. Rough cuts or holes can make the plant more susceptible to pests and diseases.
• After the first pruning, you can paint the tree trunk with white latex paint to protect it from sunburn and insects.

Create scaffolding branches for the tree. Select 4 evenly spaced branches around the trunk to form the tree's 'framework'. These branches will create structure and maintain balance. Trim the shoots on these 4 branches, leaving only one or two buds per branch. Cut just above the buds. Remove all horizontal shoots and any branches growing too close to the trunk.

• In the first two years after planting, only prune during the tree's dormant season and trim the scaffold branches to about 25 cm long.

Create additional scaffold branches in the third year. By the third year after planting, the plum tree will produce strong lateral shoots. Continue forming additional scaffold branches, evenly spaced around the trunk. Trim the upper scaffold branches to leave only one bud per branch, while leaving two buds on the lower scaffold branches. The tree should take the shape of a Christmas tree to allow sunlight to penetrate the canopy and support healthy growth.

Continue pruning the trunk. Each year, trim about 30-60 cm off the trunk to control the tree's height and encourage bushy growth near the base. Leave a leaf bud at the tip of each branch when pruning.

Continue until the tree reaches your desired height. During the first 3-5 years, keep creating new scaffold branches and trimming the trunk during the tree's dormant season. Once you're satisfied with the tree's height, switch to pruning techniques suitable for mature trees.

Prune dead and diseased branches. Every year, it is important to remove dead and diseased branches so the tree doesn't waste nutrients on them. Use a saw or pruning shears to cut off branches growing from the trunk. Make sure the cuts are clean to avoid spreading disease.

• If there are knots growing from larger branches, cut just outside the knot, about a few centimeters from the trunk.
• Dead and diseased branches can be removed at any time during the year, as this won't harm the tree.

Prune fruitless branches. If you notice certain branches that fail to bear fruit, it's time to remove them. Cut close to the trunk, as new buds on these branches typically won't bear fruit either.

Remove suckers near the base of the tree. These suckers grow from the root system around the base. Removing them allows the tree to focus nutrients on the main trunk. Use pruning shears to cut the suckers all the way down to the soil.

Prune crossing branches. Plum trees often grow new branches every season, which may cross other branches. It's crucial to prune the tree carefully, removing any branches that cross over each other. These branches can overcrowd the tree, blocking sunlight and airflow, which makes the tree more susceptible to diseases and pests.

Prune the tree in summer to limit its growth. If the plum tree is growing too large for your garden, summer pruning can help slow down its growth. Unlike winter pruning, which promotes dormancy, summer pruning reduces the energy available for growth, effectively limiting the tree's expansion during the season.

• If you prune during summer, be careful not to remove too much.
• Pruning too late in the summer may leave the tree vulnerable to freezing temperatures in winter. In the U.S., avoid pruning after July to minimize the risk of frost damage to new branches.
• Keep in mind that summer pruning may redirect the tree’s energy toward producing new leaves rather than fruit.