Answer: Lilacs are usually dependable landscape plants, but sometimes the environmental conditions aren't quite right for them to put on their spectacular displays of flowers in the spring. Lilacs prefer a sunny location and alkaline soil. In order to bloom profusely, they require a pronounced winter chill. This explains why some years the lilac blossoms are so abundant and other years they're sparce. Try pruning your lilac back a bit, to encourage new stems (and hopefully some blossom buds!), and don't fertilize it this year. Fertilizer will promote a flush of green growth, sometimes at the expense of blossoms. Supply only about an inch of water per week to your lilac this summer. By next spring it should be ready to bloom for you.
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