What do Garter, or Gardener Snakes eat?

first of all its Garter snake. I had one as a pet a few times and you can feed them mice/ baby mice (depending on size of snake) but i recommend just letting it go. you do not want it to get loose in your house! its horrible trust me. dont wait too long after capturing it to let it go because it wont be able to survive on its own in the wild. hope this helps you