This is a repost of my suggestion 6 months ago that got 10 upvotes and 1 downvote (https://ccnetmc.com/suggestions/view/1537-potatoes-growing-in-the-desert/).

Potatoes can grow basically anywhere on earth, from Siberia to Ireland to Arizona, the last one being an extremely hot desert.

Potatoes should grow at 50% in the desert to represent the (albeit few) challenges in growing them in warmer climates. This would also allow more desert towns to grow their population as desert regions on the map are pretty underpopulated.

On top of this areas on the map such as Iraq/Egypt are counted as a desert biome, even though the main areas of these countries in real life are often temperate areas that are perfectly capable of growing food, you can see this from Egypt and Iraq being 15 and 52 respectively on the top potato producers in the world.