Too Many Pumpkins by Linda White (1996)

Rebecca Estelle has hated pumpkins ever since she was a girl when pumpkins were often the only food her family had. When an enormous pumpkin falls off a truck and smashes in her yard, she shovels dirt over the pieces and forgets about them. But those slimy pumpkin smithereens sprout up in autumn, and Rebecca Estelle finds a sea of pumpkins in her garden.