Much has been written about the trend back to regional produce and the revival of Farmer's Markets in the UK. And, at this time of year in Germany, you don't even have to go to a Hofladen or Wochenmarkt. As you drive through the beautiful lush green countryside, you cannot avoid the countless little booths and stands at the side of the road selling the two main delicacies of the season: strawberries and (white) asparagus.
Of course you can buy both at other times of year, but most people tend to concentrate their consumption of these two (sometimes, surprisingly, eaten together in a rather interesting salad!) into the months of May and June when supplies are plentiful and freshness and tastiness are guaranteed.
I've often thought that seasonality is an interesting marketing approach for products outside of the food and drink arena, too. After all, we still have an internal clock that governs much of our behaviour and desire, even in these days of 24:7 365 day availability.