Persephone, the daughter of Zeus, was picking flowers one day when the ground opened and her Uncle, Hades, who had fallen in love with her, dragged her down into the underworld. Persephone cried out as she disappeared into the abyss. Her mother, Demeter, the corn goddess, heard her and ran towards her, but there was no sign of Persephone
For 9 days, without eating or drinking or changing her clothes, Demeter wandered over the world with a lighted torch in each hand, searching for Persephone. Demeter decided to abandon her divine roll as Goddess of agriculture until her daughter was found and her self imposed exile made the world sterile. So Zeus ordered Hades to return Persephone, but sadly, this was no longer possible, because whilst in the garden of Hades, Persephone had eaten a Pomegranate seed, breaking her fast and unknowingly destroying her hopes of returning to the light of day and binding herself to Hades forever. So a compromise was reached, Demeter would return to Mount Olympus and Persephone would divide her time between the underworld and her Mother.
This was why, each Spring, when the first shoots appeared in the furrows, Persephone would escape from below ground and make her way towards the sky, only to have to return to the shadows at seedtime. So long as she remained separated from Demeter, the ground stayed sterile and Winter gripped the land.