If you ever try to give them to tire centers or try to get rid of them, you will be informed that they are hazardous waste, and you will be charged a fee for each tire taken off your hands. No matter how large or small, your old tires can be recycled into raised beds.
Flowerbeds can look exceptionally pretty when planted in big tractor tires, painted white.
Spray-paint works well on tires, as does gloss paint. Alternatively, you may want to take advantage of the lowly tire's natural color, black. If you are still experiencing chilly nights at planting time, the tire, being a natural passive solar collector, will transfer its heat from the daytime sunshine, into the earth within, helping to keep your tender plants and seedlings warm and thriving. It doesn't take long to prepare and place your old tires, fill them with earth and plant them with your favorite vegetables and flowers. The depth of the tire is just right to promote good root development in all your crops, whatever you decide to plant.