I see that some people put in old stumps, partially rotten wood. From this I learned of the whole "hugelkultur" thing.

It sounds fun. If I had suitable wood I might try it in an oversized pot.

(Actually, I do have a couple inches of [partially] composted woody material at the bottom of my 10 gallon tomato pots. They seem happy.)

This post was edited by johns.coastal.patio on Sat, Apr 26, 14 at 10:58

For annuals in big pots that don't need all that root depth, you can fill up the pot with all sorts of things. Some people use bricks. Others use empty and capped water bottles, upside down plastic pots, or sheets of styrofoam insulation cut and stacked inside the pot. Logs aren't a bad idea. Whatever you use, just remember that you will most likely have to separate it from the spent potting medium at the end of the season.