My charles de joly lilac bush is a year old it bloomed this year wit tempo flowers both are now dead with no live flesh under the skin at the top should I leave them alone or deadhead them the flesh under the skin on the lower parts of where the flowers were are green and fleshy as opposed to dry and brown at the top inch or two any tips I've been told to leave it alone and am wondering will new flowers grow there next year or will it continue to rot and die downwards