Japanese Lilac tree flowering
Not turning white but stays green and falls off. Multiple flowers not becoming a tree flower. 15 years old and flowered last year.
Certified GKH Gardening Expert
Make sure your Lilac is receiving adequate water.
Water stresses can cause leaves and flowers to drop.
Pruning can rejuvenate a lilac and stimulate flowering the next spring.
Here is a link about Japanese Lilac.