We are trying something new this year with potatoes using old tires. It sounds odd, but the principle is to grow potatoes up instead of out, thereby needing less space for alot of potatoes. We started by laying one tire flat on the ground and filling it with composted material. We then buried the potato slips in it and waited for them to sprout. Once they were up, we added a second tire on top of the first and filled it with dirt just high enough that the plants peeked out the top. As they grew, we added more dirt until it was time for the third tire, and so on.

The potatoes are supposed to produce the depth of the whole stack of tires that are harvested by simply unstacking them. So far it seems to be working well and we have two towers, 3 tires high.