As someone else said Catalpa is pretty good outside. A man I know turned some large finials for the tops of fence posts some 25 years ago, they're painted white & still there. I had a big one in my yard, messy tree - the leaves [lots of 'em] are about 12", in the fall you clean them up - In the spring, the 12" long beans fall off & you get to clean up all over again.