The autumn equinox coincides with the Buddhist observance of 'Shūki Higan-e' (秋季彼岸会), when offerings are made at family graves.
Because of this the flower has, for many, come to symbolise the afterlife.
Higan (彼岸) translates as 'Other Shore', a reference to the far shore of the Sanzu River (三途の川 Sanzu-no-kawa/'River of the Three Crossings'). Similar to the River Styx in Greek Mythology, the dead would cross the river to reach the afterlife.