The NY Times recently published an absolutely fascinating map showing the distribution of organic farms as compared to other types of farm operations. It's a must-peruse for anyone bothering to read this blog. Just so cool. (Thanks to The Ethicurean for pointing this out, as we don't read the Times much)
One quick point that leaps out here is a significant reason we chose to farm in Missouri; a wide-open market. The relative saturation of small, organic vegetable farms in the Upper Midwest and New England as compared to the paucity of such things here meant we had a better chance to establish ourselves. There were many other factors as well, but this kind of thing would be well worth considering for new/young farmers looking to get started.
The other point I want to make about this map relates to the overall existence and pattern of organic farms. Notice that they exist just about everywhere. There's very little physical, climatological, or scientific barrier to organic farming. It's the baseline for how farming happened in this country prior to WWII. Where organic farms are now clustered are in the areas where consumers and/or governments are supporting their efforts and choices, not necessarily in areas uniquely suited to organic farming. The fact that New England, in a very difficult natural setting to farm, is laced with small, organic farms shows that there's no inherent barrier. The fact that Iowa, Minnesota, and Wisconsin are laced with small, organic farms shows that the Midwest is quite able to support such operations. It's a matter of consumer choices and agricultural policy that really drives the patterns of this map, and fortunately those are the things we're most able to influence.