Males reach sexual maturity once they have attained a carapace length of around 30 cm (2). Rival males will fight during the breeding season and attempt to roll one another onto their backs. They initiate courtship by a head-bobbing display and smelling the female's hind legs. This is followed by energetic circling and butting of the female's carapace. Once mating has occurred, the female lays her clutch of 3–12 eggs in a nest dug into the ground (2). Eggs are laid at the end of the wet season, between February and April, and hatch after 10 months or more (4). Hatchlings emerge within a few weeks of one another at the onset of the next rains, in November or December (4).
Radiated tortoises graze on vegetation such as leaves and grasses, flowers, fruit and cacti (2). During much of the year dead leaves also make up a substantial part of their diet (4).