update on my experiments
So I am back to the dry sand highlands. I was here last year for 7 weeks during that hot dry spell in late march early april, and planted all kinds of crops in various situations to see what would carry on with little or no attention.
The sweet potatoes, which I put the most effort into, were eaten over the summer by deer. The few that were left, probably because the foliage was less mineralized and thus less attractive, were planted in ridges of mostly sand. The tubers were very dried out, something that hasn't happened before. I surmise that the ridges get much too dry and desiccate the tubers after many months post-rain. I will plant on the flat in future.
Certain legumes were quite successful grown in lightly-amended sand with a mulch of rotted bark on top. The bark was fortified lightly with various mineral salts. Limas were inoculated with cowpea rhizobia, less ideal supposedly than standard bean/pea rhizobia but nevertheless results were very good. large quantities of dry limas which cook up very nicely and extremely flavorful. Some short-season pigeon peas performed very well also in similar conditions. Typical type cowpeas made little dry seed and what did was degraded to inedible. A small self-seeding no-name cowpea that I received from a florida permaculturalist did very well, however, super prolific. This is somewhat laborious to gather but fairly easy to shell. Pigeon peas are opposite, easy to gather and a lot of work to shell. A shelling machine is needed. Limas are fairly easy to gather and easy to shell.
Millet proved to be an excellent cover crop, along with the locally naturalized hairy indigo which became massive in mineralized areas, to some extent suppressing weeds and grass. Consequently now there is an opportunity to undersow some climbing cooler-weather crop like english peas, and irish potatoes can take advantage of ground enriched by long-season legumes.