Afterward, guests file out to throw flower petals, confetti, birdseed, or rice (uncooked for obvious reasons) over the newly-married couple for good luck.The bride stands with her back to all the guests and throws her bouquet over her head to them. Whoever catches the bouquet is the next person to get married. I don't know if this has ever been scientifically tested, but it can result in a very unseemly scramble, reminiscent of rugby scrums.