Lilacs take time to bloom and mature. Even if you purchase one in flower at the nursery once transplanted a lilac can take three to five years to settle in to flower. They also need at least 5 to 6 hours of sun and an exposed or even windy location with good air circulation. I suggest you add some Osmocote Plus to the soil at the base of your shrub in late spring to be sure it is well fed as it decides when it is ready to flower. The fragrant blooms will be worth the wait and once a lilac blooms it tends to keep flowering every spring. Sometimes gardening is about having a lot of patience. Keep growing, Marianne Binetti