Wow - that is a beautiful tree and in the photo there is not even any flowers - great winter form and great idea to use uplighting on the tree. As for your question, I would continue to break off dead branches in the spring and you may be having less flowers due to high nitrogen lawn food that encourages more leaves than flower beds. This May try adding Osmocote around the dripline of the tree. Osmocote does have nitrogen but it also contains trace elements and phosphorous and potassium that encourage more flower and fruit production. Hope you enjoy showers of blooms next year, Keep growing, Marianne Binetti