How do you grow potatoes in tires? I have three around here that are just sitting around, and thought I might try growing some potatoes in them. We have heavy, clay soil, so I can't just plant them in the ground. Two other related questions: I have some red seed potatoes. How do I prepare them for planting? Do I cut them? Dust them, and if so, with what? And what is the best medium for covering the plants as they climb? Loose potting soil? Hay or straw? Compost? Sand? The charts say that this is the time to plant potatoes in our area (zone 7). Thank you in advance for your help.