To prune gardenias, start by trimming after they have blossomed, making sure to prune the branches and remove dead growth. Gardenias need to be pruned regularly, or they can become unhealthy and overgrown. For effective pruning, you need disinfectant and pruning shears.
Prepare for the project
Before you start pruning, prepare for the project by getting an idea of how you want the bush to look. Decide what size you want. Gather your pruning tools, and sterilize them with an alcohol and water solution.
Prune the branches
Prune the oldest branches first. Cut them back to the proper height, even if it means removing a great deal of the branch. Follow by pruning the younger branches. Avoid cutting more than half of the branch off. When pruning, make sure to cut above a stem branch or leaf node.
Remove dead growth
Finish pruning the bush by removing all broken and dead branches. If the branch you are removing is dead, cut it as close to the trunk of the tree as possible. If the branch is merely broken, cut it off at the nearest healthy node.