Brian Rumsey wrote:My back yard slopes, not an extreme slope but enough that it's an issue for gardening. I'm looking at close to a 5 foot drop over 120 feet. I'm thinking of creating two terraces, an upper "yard" terrace and a lower garden terrace, supported by retaining walls. Each retaining wall would be approx. 2.5 feet. Rather than simply level my soil, I'm thinking I'd rather add new, because under a thin layer of decent topsoil, I've got heavy clay.
The obvious option is to have soil delivered from a local company, but that's a lot of soil and cost. By my calculations about $10,000 of soil per terrace for screened topsoil. I might go this route despite the cost but am interested in alternatives and/or cautions about the idea. One possibility I thought of was to do most of the leveling with wood chips that tree services will provide for free or at low cost -- perhaps something like hugelkultur -- topped by a layer of screened topsoil. But I'm thinking as the wood chips decompose, they will subside and require additional topsoil to be added. This could be a problem if I don't want large machinery driving on my ground every year or few years.
Does anybody have other ideas, or affirmations of either idea I've mentioned above? Good sources to look at for further info?