Lilacs like full sun and an exposed or windy location. They also respond to fertilizer and spring is the time to add some Osmocote around the base of your lilac shrub using about six tablespoons for a three foot shrub. Work the fertilizer into the top one inch of soil then be sure to water deep at least once a week to encourage the most new growth. If you live in a hot summer area a mulch around the roots will keep the plant cool. Also, there is a dwarf lilac called Miss Kim that stays short. Make sure you do not have a dwarf by taking a photo of the blooms and comparing to a photo of Miss Kim online or at a nursery. Keep growing, Marianne Binetti