For those of use that grow maples in containers, what is the material of choice for the planters? Plastic seems to bake the roots. Clay get heavy vary fast. Wood has the decomposition issue, and Redwood become expensive fast.
I used a lot of large, nice looking, with matching colors, clay pots, supposedly frost-proof, but after 4-5 years they begin to disintegrate (they stay out throughout the winter, I live in zone 8). Now I have almost totally switched to wooden pots. They are made of autoclave treated European pine or spruce and typically last 10-12 years before they begin to rot. One nice feature of the wooden pots is that I can screw wheels directly to the pots that go to our terrace to keep them off the ground and for easy moving. Gomero
Just a thought but have you considered the new lightweight foam planters? Otherwise if you're handy you can use the new composite lumber products, you can use them just like wood and build a nice planter, though I am not sure of the weight. Like I said, just a thought...or two.
I have made containers from pressure treated lumber left over from building a deck. I used the drops from the deck boards and used 2x4 for the frames. I mitered deck boards to form the rim at the top and used vertical deck boards to cover the 2x4 frame. I lined them with black 6 mil plastic sheeting. Be sure to cut holes in the plastic in the bottom for drainage. You can make them any size using the drops from construction projects. They fit in well around decks made of the same material. I made several 48" cubes to plant maples that I am planning to move later. Make sure that you make large ones with "feet" that will allow you to get lifting straps or a fork lift under the containers or you will never be able to move them when the time comes. An 8' maple in a 48" container is quite a load.