Generally the good deals aren’t at the centralized farmers markets. The dirt cheap deals are at the roadside stand sort of places. They’re pretty rare in urban areas like where I live now for fairly obvious reasons, but growing up in a rural area a good variety of seasonal vegetables could be found at roadside stands. They’re not really advertised, but the people in the area know who sells what and when it is in season, and it is usually just like a folding table covered in produce and a jar to put money in, all on the honor system.