>>96569560
Yeah I'd imagine something like picrelated.

With the terraces being developed over the course of centuries.
With rocks and stones removed from the soil (and used both to make the reinforcing dry stone walls and as building materials for roads and fortifications) and additional soils brought in from the digging INSIDE the hold.

Where I grew up they were mostly used for olive trees, vineyards and some stone fruits (apricots and cherries) but in other areas they were used for citruses, apple trees, aromatic trees or even just as a source of grass for smaller flocks of goats/sheep.

>>96553803
>guys who know how to make fertilizer from minerals

that's a very good point
it doesn't even require them to have any real understanding of chemistry: just knowing that certain types of rocks, when pulverized, make your crops grow better.