[patrickg_zill]

Honest question: how do German (for example) farms manage to work, since there are virtually no Mexicans in Germany?

[OliverJones]

EU. People from Turkey, Greece, and other less-industrialized parts of the EU work as migrant harvest workers (and in other laborer jobs) in the more industrialzied parts. The northern EU countries have organized guest-worker programs.

[patrickg_zill]

Is it the situation that the workers show up, do their work, are treated somewhat fairly, and then depart for their home country again?

[kps]

Subsidies and trade barriers.

https://en.wikipedia.org/wiki/Common_Agricultural_Policy

[philk10]

Eastern Europeans

[stefs]

they too use cheap labor from the east (poland, ukraine, czechia, slovakia, ...)