well he can give it up for a living, but he can still do it for himself/household.
dont need machinery and tons of animals for yourself. do it the laid back way.
And if all that don't work then I guess you could just play Harvest Moon :l.
Seriously though, it sounds like your father just does what he enjoys doing no matter where it takes him, but even if it goes down the wrong path he always manages to bounce back with something else.
I wouldn't be
too worried about him, but help him out where you can