Buttonholes Buttonholes are usually worn by the groom, the couple's fathers, the best man and the ushers. If the couple wish, they may provide buttonholes for all their guests. The groom usually wears a single white carnation to match the brides dress. The best man and the fathers wear a double red carnation and the ushers a single red or white carnation. Other colors of carnation and other flowers, for example roses, may be worn as buttonhole. Carnations are usually supplied by florists with a sprig of greenery and the stems wrapped so they are easy to fasten and remain fresh for the whole proceedings.