Radishes

Radishes are the center of the Fraggle Rock ecosystem.

Gorgs farm giant radishes in their garden in order to make Gorg Youth/Beauty Cream. Without this cream, Gorgs would become invisible. Junior Gorg also considers the largest radish in the garden, Geraldine, to be his friend.

Fraggles depend on radishes as their main food source. They must sneak into the Gorgs' Garden to obtain radishes (this is Mokey's job), frequently leading to conflicts with the Gorgs, who view the Fraggles as garden pests.

Doozers have a constant drive to build, and their building material, Doozer sticks, is derived from ground radishes mined from beneath the Gorgs' Garden. Fraggles eat Doozer constructions.

The dependence of all three species on radishes was explained to the viewer in Episode 119: The Great Radish Famine, in which Marjory the Trash Heap tried to bring the Fraggles, Doozers, and Gorgs together by making all the radishes disappear. The characters themselves did not figure out the connection until Episode 511: The Gorg Who Would Be King.

Before the discovery of radishes, Fraggles ate mushrooms (Episode 315: Born to Wander), and Doozers built using turnips (Episode 319: The Cavern of Lost Dreams).

Outside of Fraggle Rock, Splurge from Hey Cinderella also has a penchant for radishes.