Poppies

Represent Eternal Sleep

Because of the narcotic properties of the opium poppy, it is most commonly associated wih sleep and death and with Morpheus (the god of sleep and dreams), and because of its large seedpod, Demeter (the goddess of fertility and agriculture). 

It has also been used to symbolize extravagance and ignorance.

Sometimes the poppy is used as an attribute of Christ's Passion because the bright red color of some of its flowers is used to symbolize blood and death. 

In the Middle Ages, Christians gave the poppy some of the same attributes as ripe ears of corn, in a sort of symbolism by association since the red corn poppy grows in the the same fields.