Planter that fits around 6x6 post
We have a patio area under a large deck. We would love to have planters at the base of all the posts from the deck above. Does anyone know of a source for planters that will fit around a 6x6 post? I have seen split pots for 4x4's but nothing bigger. I needs to have an interior sleeve so the wood post will not rot from the soil. Any help will be greatly appreciated!