Used tires in gardening?

Used tires in gardening?

Years ago, someone dumped a truckload of used tires on our land. (Rednecks are awesome!) I have an idea of using those tires as a border for a small raised garden in a corner of my yard. I plan to stack them two high, and make the tires themselves a sort of planter for tomatoes, rosemary, etc. My question is: Is this insane? Am I setting myself up for leaching chemical problems? Thanks for your input!
shameful confession

shameful confession

The bishop

The bishop

Pics and questions

Pics and questions

Care of lemon myrtle

Care of lemon myrtle

New Apartment from Haifa, Israel

New Apartment from Haifa, Israel

Request!

Request!