Prune the tree when it is dry outside to prevent disease.
May 25, Removing Dead and Diseased Branches 1. Prioritize dead and diseased branches over healthy branches. With magnolia trees, removing healthy, if unattractive, 2. Wait until the magnolia tree 90%. Sterilizing the tools beforehand can be beneficial for the tree. When pruning a magnolia, it is advisable to begin by removing any dead, broken or sickly limbs from the tree, not just for aesthetic purposes but to improve overall health and well-being.
After this, limbs may be trimmed.