Answer: It isn't unusual for some types of lilacs to take 7 years before they bloom. From your description, I'd say you're giving your lilac all the TLC it requires and you only need to wait patiently until it's mature enough to bloom. By the way, the best bloom in lilacs happens after an especially cold winter. This explains why some years lilacs bloom profusely and other years the blooms seem sparse. Good luck with your lilac!
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