Minecraft wiki entry for Shelters, associated text: A Zen Garden is for aesthetic purposes only. A Zen Garden is made by choosing the place where you want it to be. Then make the walls surrounding the garden with any material you like. I like to use leaves or maybe cobblestone wall. Then fill the walled up space with any kinds of trees, flowers maybe melons, pumpkins, sugar cane, mushrooms and maybe even a small fountain. Do whatever but try to make it as natural as possible. I don't recommend to build this in multiplayer because griefers can find your house more easily but there is the exception of Faction servers in which you can claim land or servers in which you can buy a block that protects a radius.