"What year is it?"

There essentially two varieties of tortoises that you can have as a pet, the kind that do not hibernate (tropical) and the kind that are huge pains in the ass (non-tropical).

If you have the latter variety, then you're gonna have to jump through all manner of hoops for several months out of the year, as the guy in this video explains:

This guy actually gets off kind of easy, only having to care for a tortoise in a box from the fall until late winter. Species that are indigenous to locations far away from the equator can hibernate for up to eight months out of the year. That's a full two-thirds. It's almost like not having a tortoise.

Sources: Neil Slorance | h/t Laughing Squid