Back in the good old days, farming was easy. Throw some seeds in the ground, keep it watered, pray to your preferred deity to spare your crops from pestilence and wait for harvest season. But with the global population closing in on 7 billion mouths to feed, humanity is going to have to figure out how to grow more food using less land and fewer resources, and soon. So while some researchers and equipment manufacturers are devising intelligent agricultural implements that will toil in tomorrow's fields on our behalf, others are aiming to bring futuristic farms to urban city centers."Over three billion dollars were lost in California alone [in 2017], because there's not enough people to actually do the operations in seeding or harvesting," Brandon Alexander, co-founder of Iron Ox Robotic Farms, told Engadget. "The average age of the farmer now is 58. And so one of the big issues just plaguing farming is that there's just not enough labor to go around. The problem is getting worse every year."Vertical farming is the practice of stacking plants above one another to grow in a closed and controlled environment. Among the earliest imaginings of these agricultural towers can be seen in a 1909 Delirious New York passage extolling "the Skyscraper as Utopian device for the production of unlimited numbers of virgin sites on a metropolitan location."In the years since, vertical farming in the US has become a robust, albeit auxiliary, part of the national agricultural system. According to a 2017 report by Agrilyst, roughly half of all indoor farms rely on hydroponic setups, another quarter prefers soil and the remainder use a hybrid system of the two. Interestingly, roughly half of the indoor grow operations in the US (43 percent) are in urban areas. The five primary crop types currently being grown in these farms are leafy greens, tomatoes, flowers, microgreens and herbs (yes also those herbs)...MORE