Hi, My name is John and I am going to list the materials required to start building your first Walapini. The wala what? It is better known as a pit greenhouse, but we have tweaked it a bit for reasons we will discuss later. First you will need a location or land according to your needs. For sake of time we will build in the back yard and use a 10' by 16' rectangle. You will want to acquire as many tires as you can. I started out with 45 you will need more as your size increases. You will want a shade free area and you will orientate a long side facing south. This is for maximum solar gain. You will need shovels and sledge hammers. You will dig out a hole in the ground according to your size and at least 6' down. You will then lay your tires in a line around your rectangle and fill them with dirt or sand. You will spend most of your time pounding the dirt into the tires until they swell. You will lay them like bricks, one atop another around the perimeter. When you are done you will be surrounded by a wall of tires on all four sides up to ground level. Check out this video.
Thank you and enjoy,