Both of the above responses are good advice. The sawmill I go to locally sometimes has a bin of short boards (around 2 ft) that you can mix and match any 7 boards for $25. I could get enough wood for around 40 pots there for $25, and it was top quality kiln dried lumber. Also for comparison, woodcraft sells cherry for $9.99 per board foot, and my sawmill sells it for $3.80.