May Lily of the Valley & EmeraldBy sheer popularity, the lily of the valley is the flower of the month most commonly associated with May birthdays. It was first chosen by the Victorians to represent the month because they appreciated its delicate scent and curving stems and associated it with vitality and peace. . People born in May are considered to be humble and virtuous, and the white bell shaped flowers of this plant send that message loud and clear to anyone viewing the blooms.