that is a new one on me.
Can you describe that process? How is the tire cut, around the circumference ? creating two rings?
Living in Bubba country, I thought that I had seen all possible uses for old tires! :)
I put the first tire on a patch of dirt, or if you need to do it on grass, then put down a thick, wet layer of newspapers on the bottom. Fill half way with a mix of soil & compost, then put in 4 or 5 potatoes, either whole or pieces that you’ve cut with at least two ‘eyes’ on them, and have allowed the cut sides to dry for a few days.
Then, fill in with more dirt and keep watered. As the plants grow, throw on tire ring after tire ring, continuing to fill with dirt, leaving about 6” or so of leaves above ground. Potatoes need a full sun spot to grow in, so 6 or more hours of sunlight a day is best. Keep them watered. I didn’t fertilize mine at all this season.
I have a ring of three tires this season, but in years past we’ve had them as high as six.
After the plants flower, and then die back later (September, here in my Zone 4) you just push over the tires and harvest your potatoes.
I planted German Butterball, which is a tan skinned, yellow fleshed potato.
Don’t use store-bought to use as they do spray them with a sprouting inhibitor, but if you leave potatoes in a warm-ish dark place, they’ll sprout no matter what. Then you can use them. :)
Watch out for Colorado Potato Beetles, though. If you plant them, they will come. You can use an insecticide on them, or just pluck them off as you see them; they’re bigger than ladybugs with a yellow and back striped back and a reddish head. You can’t miss ‘em!