The groom, groomsmen and fathers of the bride and groom typically wear buttonholes. They need a stiff suit jacket to stand up well so more casual weddings with just a shirt are better off without them. Men’s buttonholes are worn on their left jacket lapel with the stem facing downwards. A single flower on a leaf is common but adding extra blooms for the groom or all the boys can be a nice difference.
Mums can be treated special with a corsage. Lapel corsages are worn in the same place as the men’s buttonhole, but are more detailed, with some pretty ribbon and extra blooms. They are worn so that the stem faces upwards. Wrist corsages are also a popular alternative. Worn on a bling or pearl band for that extra ”wow” or just tied on with ribbon they can start from a few blooms to something much larger with lots of blooms, leaves and fillers.