I tried tomato spikes one time outdoors, it didn't work well. But if you have some extra seeds hanging around, I'll bet that the compost pile might work well enough for a go. Not much down side to trying, if you have some seeds that didn't cost an arm and a leg. Having some RotBlock in hand might be a good idea.
Good luck wiith it.
It would be a cool experiment. I'm sure it would be productive and very easy. It really should be a water only set up.
When we legalize, I'll surely do it.