Pruning Flowering Trees

Posted on: 28 June 2021

Flowering trees add grace and beauty to a landscape. Proper trimming and pruning are a must to ensure the trees reach their full blooming potential.

New Vs. Old Wood

Flowering trees produce flower buds on either old wood or new wood, depending on the tree variety. New wood flowering trees usually start to bloom in late spring or early summer, typically on buds formed in the early part of spring. Some varieties may continue to bloom repeatedly throughout the entire summer. Hawthorn, crepe myrtle, and hydrangeas are examples that flower on new wood.

Most varieties that flower on old wood are those that are some of the first to flower in spring. This is because they set their flower buds the previous summer and fall. The buds will stay on the tree during the winter and then burst into bloom, often before the leaves even have a chance to appear. Examples of old wood flowering trees include quince, mountain laurel, and rhododendron.

Trim Timing

Once you know whether a tree is a new or old wood bloomer, you can decide when to prune. New wood bloomers are best pruned in very late winter or very early spring. The buds should be swelling, but there should be no leaves or flowers yet as the tree is still in dormancy. Dormant pruning reduces shock to these trees and typically won't affect flowering, since no flower buds have yet formed.

Old wood bloomers can't be pruned until after they have flowered, otherwise you will inadvertently prune off all the flower buds before they have a chance to bloom. The best time to prune is after the last blush of flowering but before the tree begins to set new buds for next year.

Pruning Tips

Don't be afraid to drastically prune if a tree is overgrown. It will often respond to hard pruning by putting out new branches and flower buds for the next year. Just make sure to remove no more than about a quarter of the branches on the tree, as more can shock the plant.

It's also important to keep in mind that although spring pruning can reduce flowering on old wood trees, it won't typically harm the tree. If an overgrown tree needs some shaping done to improve its structure, the dormant late winter period is typically ideal since you can clearly see the branch structure. Shaping at this time may reduce blooms for one year, but the healthier structure will provide even more flowering thereafter.

For more tips about the best time to trim your blooming tree, contact a local tree pruning service to learn more.


Keeping Your Trees Healthy

About a year ago, I realized that our front trees were starting to look a little funny. Some of the leaves were wilted, but we weren't anywhere near autumn. The bark on the trunk also seemed to be rotting away, which was frustrating and disappointing. Fortunately, a friend of mine told me to call a professional arborist for help. He came out, inspected the trees, and injected some special pesticides into the trunk. Within a few months, they started to look a lot better. Our arborist also trimmed our trees to reduce the weight load on the branches and to improve their shape. Check out this blog for information about tree trimming.