I spent a lot of hours and a lot of words exploring the world of vertical farming over at TechCrunch. The research, which resulted in this feature, was bookended by conversations with Dickson Despommier, a former Columbia University professor now regarded as the godfather of vertical farming. This final discussion with Despommier is a kind of coda to the piece, exploring his seminal book, The Vertical Farm 10 years after its initial publication. You can read a writeup of the full interview over on TechCrunch.