Depending upon environmental conditions, the optimal growth of lilacs is moderate, at an annual rate of 13 to 24 inches. They reach a final height of up to 15 feet, according to the Arbor Day Foundation.
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In Jacksonville, Fla., Frank Whittemore is a content strategist with over a decade of experience as a hospital corpsman in the U.S. Navy and a licensed paramedic. He has over 15 years experience writing for several Fortune 500 companies. Whittemore writes on topics in medicine, nature, science, technology, the arts, cuisine, travel and sports.