I read somewhere it would be best to just plant things I like, and not to worry about whether or not it was overly cost-effective. I already planted some corn, green beans, peas, and carrots in the spot I marked, and they're working out pretty well. I planted those from seed, and they've done well. On a whim, I planted a single potato that had sprouted eyes and now have a 4 foot high tower of 6 potato plants.
Instead of building up the tower with wood, I cut and split some wood from an unidentified conifer tree I dropped earlier in the spring.