Pham Thi Huong went from the backbreaking job of coaxing coffee out of Vietnam's central highlands to an inconceivable one: growing strawberries on rocks. Huong and her husband threw in the shovel on their days of toil at the mercy of volatile commodity prices in 2019 and joined vertical agriculture company Orlar. Now they work together at a greenhouse where connected white pillars line up like library stacks, each one holding rock on top of rock. The rocks are treated with a patented mix of microbes to sustain plant life. Romaine lettuce, basil, bok choy and flowers burst from the stones. "I thought, with technology like this, we can develop more," Huong added, noting a further bonus: the use of far fewer chemicals than in traditional agriculture. Huong's move is part of an expanding agricultural revolution in Asia that aims to feed a ballooning population against a backdrop of formidable problems.