The history section enables you to keep a history of all plants that passed away. You can think of it as a place to dwell in memories. You can actually give this section a custom name, like Compost, Cemetery, Hall of Shame, The Void or whatever else. Plants that are moved to this section will not appear in any locations/rooms and are not counted in stats. You also can't view their details anymore. If you mistakenly moved a plant to this section then you can undo that. There is also a sorting and filter available as well as a calendary list of years where plants have been moved to this section.