We're going to enclose the small area of the yard where we built the SFG box ASAP. That will solve the dog problem, but in the meantime I wanted to get some of what I bought into the ground. Keeping in mind that Mel says it needs to be 6-8 inches deep, and can have a solid bottom, I am experimenting with these:
The boxes are 7 inches deep. The mix settled a bit so I will add more. So far they seem to be doing fine. The onions are so close together because we planted them too late to get big bulbs anyway, so we're using them as green onions (in which case they can be planted that close together). The tomatoes are grape, and need to be staked soon. There are a few extra onions in the box with them, but they needed more space.
It's kind of an expensive option to do too much with, and not very pretty, but it seems like it will work.