Green beans and other vegetables growing in the computer-controlled climate of a hydroponic farm in an old shipping container at Boston Latin School. Students monitor and control it all, on site or with a mobile app. (Chris Berdik )
BOSTON – On the cramped urban campus of Boston Latin School, high-school students grow an acre’s worth of vegetables in an old shipping container that’s been transformed into a computer-controlled hydroponic farm. Using a wall-mounted keyboard or a mobile app, the student farmers can monitor their crops, tweak the climate, make it rain and schedule every ultraviolet sunrise.
In a few decades, nine billion people will crowd our planet, and the challenge of sustainably feeding everybody has sparked a boom in high-tech farming that is now budding up in schools. These farms offer hands-on learning about everything from plant physiology to computer science, along with insights into the complexities and controversies of sustainability. The school farms are also incubators, joining a larger online community of farm hackers.
“We are constantly experimenting,” said Catherine Arnold, a Boston Latin history teacher who oversees the environmental club that runs the farm as an extracurricular activity. It was built by a Boston startup called Freight Farms, which “upcycles” discarded shipping containers into “Leafy Green Machines” for small-scale growers and restaurants, as well as a dozen schools and colleges.
The latest version of a freight farm costs $82,000. Boston Latin has a cheaper, earlier version, paid for with a green-schools grant. The students have been giving their food away but plan to sell produce to parents and neighbors this year, to cover the annual cost of seeds, nutrients and other supplies.
On a recent morning, Arnold showed off rows of spinach, peppers, tomatoes, lettuces, green beans and herbs hanging below drip irrigation that was bathing the roots in a recirculating mix of water and nutrients. The plants grew out of a recycled plastic mesh rather than soil and were lit by thin strips of LED lights.
When the school’s farm opened in 2014, Freight Farms staffers taught students about crops that have a proven hydroponic track record and their preferred mixes of temperature, nutrients, moisture and other factors. But Arnold said the real learning comes from trying new things.
“They never said you can grow green beans, but we have two varieties,” Arnold said. “This year, we’re going to try carrots and turnips. Anything the students want to try, we’re going see what happens.”
A video camera and sensors send real-time data about the growing environment to a computer that triggers farm systems set to schedules and thresholds (such as carbon dioxide or nitrogen levels). Students monitor and control it all, on site or with a mobile app. According to Graeme Marcoux, a high-school environmental and marine science teacher in Salem, Massachusetts, whose school set up a freight farm last spring, the remote access is essential, because only so many students can work inside a 320-square-foot box, and because farming doesn’t stop when the bell rings.
“My students can collect data on the farm from anywhere, whenever they want to,” said Marcoux, who teaches a vocational course (worth one science credit) in hydroponics and aquaculture.
Besides passing on technical knowhow, Marcoux encourages class debates about food sustainability. The many high-tech automated “vertical farms” popping up in cities around the world have a shared mission of growing more food locally, while using a lot less land and water than conventional farms. Being indoors means no pesticides, and their closed systems mean they don’t poison waterways with fertilizer runoff.
But critics say that indoor farms are energy hogs. A farm like the one at Boston Latin, for instance, uses enough energy to power about two and a half American households. Of course, conventional agriculture also has many hidden energy costs, from shipping food, refrigerating storage facilities, manufacturing and operating massive farm equipment, and moving and treating all that irrigation water. Plus, rapid gains in LED efficiency and renewable energy will help shrink the carbon footprint of indoor farms.
“It’s a great debate to have with the students, because by the end of that debate everybody has a much deeper sense of what actually makes something sustainable,” said Marcoux.
The Freight Farm app links to a repository of articles about everything from crop scheduling to food safety. There’s also a Facebook group of freight farmers who are a ready source of ideas and advice on topics such as how to deal with tiny spots on your lettuce or how best to keep the humidity under control.
The potential of networked farmers swapping expertise and experimental results – call it crowdsourcing crops – is also at the heart of OpenAg, an initiative of MIT’s Media Lab, led by research scientist Caleb Harper. In 2015, the OpenAg group gave a handful of local schools prototypes of their “personal food computers,” which are tabletop hydroponic farms that users program with “climate recipes.” Every recipe, as well as the user-interface code, is open-source and posted online for use by a global community of green-thumbed hackers.
One of the early food-computer recipients was the Shady Hill School, a private preK-8 academy not far from MIT in Cambridge, where students grew basil, sage and various leafy greens.
Every grade had some access to the food computer. The first-graders, for instance, featured it in their “farm to table” unit, alongside food grown in an outdoor garden.
“They could not only measure the plants, they could see and measure the growing roots,” said Will Borden, Shady Hill’s director of academic technology.
“To imagine you could help feed people with this computer was amazing to these kids,” he added. “Most of them don’t think about technology and food going together, when clearly they do, even in traditional farming.”
The food computers for the pilot schools came pre-assembled. But for everyone else, they were totally DIY, using downloadable step-by-step instructions. For example, James O’Brien, a senior at Staples High School in Westport, Connecticut, was inspired to build a food computer after watching a Caleb Harper TED talk on YouTube last summer.
On his own, O’Brien machined and assembled the parts, bought the sensors, wired them into a circuit board, and programmed the computer’s brain. He demonstrated his food computer and the lettuce he grew with it to middle school kids at a summer camp run at a local farm. In August, he started a nonprofit called Workshop Garden Technologies to create after-school programs for middle-school students using food computers.
OpenAg is now readying a more refined and user-friendly kit version of the food computer for a second round of school pilots planned for the spring. It will also be possible to program the “climate recipes” with a simpler, block-based coding language, such as Scratch (another Media Lab creation).
There will still be a strong DIY element, however. The idea is that lesson plans, like climate recipes, will be created, shared and improved upon by the community of school food-computer users.
“We want to include kids in a co-creation process, to let them play with the food computer and help us improve the engagement and experience of growing with it,” said Hildreth England, OpenAg’s program coordinator. “Kids are natural tinkerers. It’s a perfect fit.”