Google Insights is one of Google's beta projects which tracks the change in the number of searches over time. Just for the heck of it I used it to search for "organic farming". I expected to see a steady rise, as it seems the subject is getting more and more attention. But, no--see this
The US isn't in the top countries and the interest seems to be declining gradually. Of course, one swallow does not a summer make. Maybe the Obama White House garden caused "organic garden" to show an increase? Here the trend line is flatter, and the US is in the top 3, but Obama doesn't seem to sparked enough interest to change the trend.