Go to the grocery store and take a look at the produce. Lots of stuff that looks a day or two old at best. Now read the little signs that the store puts next to each vegetable or fruit. Product of Mexico.
How long does it take to get a bunch of celery from Mexico to my town in Idaho? The stuff has to be picked, and then packaged or processed, and then delivered. I say a few days at best.
What kind of rules are there in Mexico that govern the growing of crops? I have a guess, and it is not good.
Buy local and know your farmer. Know how they grow the stuff. See the crops come out of the ground.
Join a CSA today!