When we grew and sold organic vegetables we would usually pack them into boxes, take them to the depot which would then ship in refrigerated trucks our boxes along with conventional produce 300 km to the wholesale markets. From here the fruit and vegetables were moved, again in refrigerated vehicles all over Queensland. In the case of our organic vegetables throughout much of Australia.
One day, having spare produce to sell we took it to the town 100 km north only to find that the Health food store already had had a delivery of "excellent quality patty pan squash". We asked to see the box to compare our quality and , yep, it was our squash. By now it was getting slightly the worse for wear after a round trip of al least 700 km.
It occurred to us that although we were doing something environmentally worthwhile by using organic growing methods, we were not helping in the wider sense of reducing transportation costs.
We sold some of our produce at local markets and determined that that was the most sensible way to go. Selling in local markets or roadside stalls has a drawback - while selling one is not growing so we had to work out a sensible balance.
My recommendation? Support organic growers but support them through local farmers markets if possible.