Only the center of a potion generator needs a valid tile, so you can do stuff like this, or even have the potion generators overlap a fair bit.
Viewing post in My Little Potion Factory jam comments
Thank you so much for playing and for the feedback! I was aware of the overlapping being a thing but I felt like it could make the player able to make some kind of generator clusters. However I was not expecting the chests being placed that way lol. I will patch it after the jam to fix all overlapping, that would make more sense. I'll had that to my todo list. Cheers!