After World War II, the same atomic power that leveled cities was repackaged for backyard gardeners hoping to grow exceptionally large peanuts. This episode explores atomic gardening, a strange and very real movement born from the Atoms for Peace optimism of the 1950s, in which seeds were bombarded with gamma radiation to force rapid mutations. We explain the science of the five-acre gamma gardens, the cobalt-60 source at their center, and the Goldilocks zone where useful mutations emerged.

We follow the craze from government labs to the public through Muriel Howarth's Atomic Gardening Society and a Tennessee dentist who irradiated millions of seeds in a backyard cinderblock bunker. Though the amateur experiments failed and the romance of the atom faded, the professional work succeeded spectacularly, producing more than 2,000 plant varietie ...