Q.Japanese Tree Lilac
Hi, we planted a JTL in the early summer of 2015.. it had some nice blooms on it at that time. No blooms in 2016 ,or 2017. Ant ideas you can share with us on how to encourage some beautiful blossoms? It seems to be growing nicely otherwise.
Much appreciated
Charles Michaud
Liverpool, NY

Lack of flowering may be due to several factors. While Syringa meyeri 'Palibin' will flower when quite small, many lilacs won't bloom for 4, 5 or more years after planting. Lilacs and most woody plants must grow and mature before they are capable of blooming. Exposure also could be a factor. Lilacs need at least 6 hours of sun to bloom well. Improper pruning is another possibility. Many lilacs bloom on the previous season's growth. The flower buds form during the summer months. Pruning lilacs in fall or late winter could remove much of the blooming wood. There is little that an individual can do to encourage lilacs to bloom. Fertilizing the shrubs encourages vegetative growth, but may actually delay flower formation.
https://www.gardeningknowhow.com/ornamental/shrubs/lilac/japanese-lilac-information.htm