[cm2012]

I remember one noble solved this in a clever way. He made it illegal for peasants to grow potatoes, and grew them in the his royal garden. Then peasants would smuggle them out in the night and grow them back home, thinking if it was forbidden it must be good.

[eftychis]

This legend or similar exist throughout European countries. I am not sure how based in reality they are, but there must be fragments of truth, or common approaches that were later exaggerated.

[maxnoe]

That's attributed to Friedrich II, king of Prussia, however might just be legend:

https://de.m.wikipedia.org/wiki/Kartoffelbefehl

[thaumasiotes]

https://satwcomic.com/can-t-touch-that