When and how should a red tip photinia plant be trimmed? Mine are about 15' high and are planted between a fence and shed (about 4' apart).
Pruning a Red Tip Photinia
Certified GKH Gardening Expert
Prune photinia sometime during early spring through early fall--late spring, early summer being the best time. Unruly plants can be cut back 6 inches to the ground and will come back--annual pruning will help keep them maintained and manageable. They can take a pretty severe pruning, so you can cut them back to a manageable size without harming them. Here is more information: https://www.gardeningknowhow.com/ornamental/shrubs/photinia/pruning-photinia-shrubs.htm