I use cushion planters - cut out polyurethane foam cushions. You can leave the
bottom in or not as you choose. Of course, you can custom make the soil. I use
amended garden dirt generally. They are great for low growing plants - thymes,
parsley etc. Some look like rocks; others are less attractive.

They are not ugly like garden tires. Has anyone tried tires painted with
roofing cement and then covered with peat moss and other materials.