[carapace]

I haven't done anything quite that sophisticated! I have only "anecdata" to contribute.

We are basically on sand dunes here and our "soil" is what I call "dirty sand". I had a bunch of wood chips with some chicken manure and feathers in it and I spread that about six inches deep over a bare patch of sand. I added potatoes and kept it moist. Now, a year and a half later, there's a layer of rich living soil between the sand and the wood chips. There are lots of worms and other critters living in there, and I have plants growing well. It's January and I've got broccoli, blooming nasturtiums, fava beans, and potatoes of course, plus a lot of other things. Mushrooms appear regularly too. I don't add any fertilizer or anything.