3-4 years? Several thoughts come to mind:
By the time it was ready for harvest, I would forget what I was growing.
Imagine the boredom of 4 years of only mowing road banks.
You could take a really long vacation.
I can hear it now: "Honey, since you aren't doing anything for 4 years, can you help me with some projects around the house?"
No way am I growing that stuff.