The boutonnière is worn on the left lapel of a men’s suit, sport jacket, or blazer jacket; it can also be worn on an overcoat. The boutonniere is always attached above a man’s heart, and it should be worn in the lapel’s buttonhole, a 1 to 1.5-inch opening that is a vestige of when a man’s jacket lapels closed to protect his neck. Only on higher-end suits will you see the lapel button-hole present, functional, with a latch and built strong enough to support the flower