I have to admit, I find these recycled tire planters charming. Planting containers made from tires are pretty easy to make and cost almost nothing. Since it costs to dispose of tires, getting a few used wheels from a local auto shop should be a snap.
two and a 1/2 wheels, old piece of flat steel and 16" of pipe from from an old drive shaft, I welded 3 bolts on the right side of the steel plate to hang BBQ tools. Just don't use gasoline to start it!
Wet down the wheel and tire, then spray or brush on the wheel cleaner. Use a soft brush to get in where the brake dust hides, then hose down. Lather, rinse, repeat--then dry the water spots off with a clean towel. Follow up with car wax. http://www.millsmotors.com/