The Flowers, known sometimes as the Flowers-that-be, or simply Upstairs, are the sentient vegetable entities which run the PPC. They are not all Flowers -- some are trees, at least one was a fungus, and one is a lichen -- and may or may not still be their natural sizes. However, they are all highly intelligent and powerful psychics (some are stronger than others, obviously, but it isn't known how strong they are on average). Most Flowers are roughly man-sized (six to seven feet tall). According to one story, Flowers eat what appear to be blue-green crystals, though it is unknown how exactly they do so without any mouths or digestive systems.
The Flowers are distinguished from their unintelligent cousins by the use of capital letters -- clover is a three-leaved plant with white flowers which grows in fields, while the Clover is the Head of the Department of Finance. Where a Flower is given a name apart from its species -- the Sub Rosa, Captain Dandy, or of course the Sunflower Official -- this indicates that they are one of the first generation of Flowers. It is currently unknown why only the Firstborn have names.
The Flowers came into being on Origin, through a complicated series of events involving astronomically unlikely coincidences which the Legal Department would surely not have allowed had they been in existence. They were the founders of the Organisation which became the PPC, and constituted its original Agents. With the destruction of Origin in the Cascade, it is believed that the Flowers working for the PPC and League of Mary Sue Factories are the last survivors. This could be incorrect, however.