The Chinese Turn Their Rooftops (and Closets) Into Minifarms

Roger Mu, an entrepreneur from Texas now living in Shanghai, scoured local markets for jalapeño peppers but to no avail. Homesick for homemade salsa, he eventually decided to grow his own. Since he was iving in a cramped Shanghai apartment with no outdoor lawn or garden, this wasn’t a simple proposition. But he did have some space available: in the closet.

Mu studied manuals about hydroponics, a technique for growing plants that doesn’t require soil but rather uses nutrient-infused water to deliver plant nutrition. The plants’ roots find support by growing around pebbles, sand, woodchips, or anything granular they can weave around, rather than soil. It’s perfect for limited space—and limited small-scale farming. Mu used a special light borrowed from a video-production company to jump-start photosynthesis.

The first batch of 60 peppers turned out to be delicious. Next he tested his technique with heirloom tomatoes and cucumbers. Success—he had everything he needed to make the perfect salsa. Mu also realized that his homegrown vegetables were healthier than many store-bought options. “Food safety and quality in China is a bit iffy,” he says, “considering all the pesticides, fertilizers, and pollution dumped into fields here.”

In recent years, food-safety scandals have rocked Chinese newspaper headlines. Last spring, the government of Guangzhou, a southern megacity, announced that 44 percent of rice tested in local restaurants was contaminated with the heavy metal cadmium, which can cause cancer and brittle-bone conditions. In June, China’s environment ministry revealed the sobering results of a national five-year soil survey: 19 percent of China’s agricultural land is polluted.

Amid rising public alarm about soil pollution, Mu easily found other Shanghai residents interested in growing their own food. He soon teamed up with David Li, a Taiwan-born software engineer, and others to rent rooftops of downtown commercial buildings for urban gardening. “The limiting factor in most urban environments is light, but a rooftop has relatively few obstructions [to] direct sunlight,” Mu says.

On a Saturday morning in late May, Li and a handful of volunteers met at EcoVillage, a Shanghai shopping complex that counts among its tenants environmentally friendly clothing shops and organic eateries. Together the volunteers assembled a self-watering tomato planter, using a plastic bucket, mashed coconut shells, and a few simple supplies from a hardware shop. “The beauty of this design is that you only have to check on the water once a week,” says Li, who recognizes that busy work schedules don’t allow most people to wander far from home or the office to check on plants daily.

Mu and Li have also set up cooperatives with local farmers on the outskirts of Shanghai to grow vegetables in greenhouses that don’t use pesticides. “We pay a premium to have a direct relationship with the farmer and specify the exact growing conditions,” Mu says, “but when it comes to better health, more and more people are willing to pay for it.”

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