Se more details and mod links here: https://digineaux.com/farm-everything-everywhere-including-deadzones/

This Kenshi mod makes farming viable in every region, freeing up some new base locations and enabling the player to do more in a single playthrough. Every zone that normally has 30% or less, now has 30% fertility . If it was 30% or lower, but still higher than another fertility type in that biome it’s now 50%. Biomes with 0 fertility now have 10-20% fertility.