Radishes are the center of the Fraggle Rock ecosystem.
- Gorgs farm giant radishes in their garden in order to make Gorg Youth and 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. They did this so the Fraggles will eat Doozer constructions.
The dependence of all three species on radishes was explained to the viewer in the first season episode "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 the end of the final season, in "The Gorg Who Would Be King".
Doozers also attempted to use radishes for entertainment with radish-rolling races in the storybook Cotterpin's Perfect Building.
A Sesame Street sketch involving Beginning, Middle and End makes reference to a "Magic Radish" while Middle is telling his part of the fairy tale-like story, and episode 2957 features Telly Monster expecting a visit from Radish Dude.