I have a very beautiful but very large plant (10 feet tall) - I would love to be able to prune it very hard rather than get rid of it, which is the other option. It is currently shading out too many plants and needs really radical pruning. It is in beautiful full flower at the moment. Advice, please.
Right after blooming is the time for major pruning. You can take out no more than 40% of the leaves during any one pruning without causing severe stress to the plant. Start with the largest, thickest branches and cut them to the ground. Trim to control height but keep the 40% in mind. Every year thereafter, take out 1/3 of the stems to the ground.