Freight Farms is a Boston-based startup that takes refrigerated shipping containers and repurposes them as indoor hydroponic gardens. Each sustainable food growing unit is known as a Leafy Green Machine. Its footprint is smaller than the end zone of a football field, yet it is capable of growing as much food each year as a traditional farm the size of an entire football stadium — about 1.7 acres. Because the whole operation is contained in a standard-size shipping container, food can be grown anywhere a container will fit.
On December 4, Freight Farms held a presentation for Rhode Island educators at the Cumberland High School in Rhode Island, where one of its Leafy Green Machines was installed at the beginning of the school year. It takes about 4 months to get each unit fully productive. Harvesting of the first vegetables has just begun, with more sustainable food being planted every week.
Freight Farms has been in business for about two years and is always updating its systems to make them more efficient. The container is completely refurbished on the outside and repainted in bright green and white. Inside, everything is immaculate, with work stations in the front and four vertical growing racks in the rear. Once everything is set up, it takes only about 20 hours a week to run the farm and tend to the 9,000 plants inside. Work schedules can be prepared weeks, months, or even years in advance.
Freight Farms uses LED lighting exclusively. Not only is it energy efficient, but it also provides the light in the visible red and blue spectrum plants need to thrive, along with a smidgen of ultraviolet and infrared. Water usage is closely monitored, with almost every drop accounted for. Each week, only about one gallon a day is consumed.
The growing process begins with a seedling tray about 18″ long and 12″ wide. It is separated into 200 small compartments with a bit of soil in each one. One seed goes into each compartment, then the tray is watered with a special cocktail of nutrients customized to each variety of plant being grown. Then it is covered and placed on a shelf underneath the preparation area. After two weeks, the seedling tray is moved to the middle shelf, where the bottom is immersed in nutrient-infused water.
Two weeks after that, the sprouted seedlings are transferred by hand to vertical growing racks that attach to an overhead rail system that shuttles them back to the growing area in the rear. When the plants are finished growing, the growing rack is moved back to the front work station for harvesting. The whole process is largely automated and can be monitored and controlled remotely using a dedicated smartphone app developed by Freight Farms called “farmhand.” Each Leafy Green Machine can grow up to 4 tons of fresh vegetables every year.
Because each Leafy Green Machine is fully insulated, only about 120 kWh of electricity per week is needed for heating and cooling and to run the lights and pumps — about the same amount a family of four uses. The temperature inside is maintained at 60ºF. Andrew McCue of Freight Farms says Leafy Green Machines go about their business of producing fresh, sustainably grown food whether the outside temperature is below freezing or over 100 degrees.
Only half the growing space inside the container in the parking lot at Cumberland High School is being used at present. But there are several more seedling trays that are almost ready for transfer to the growing racks and the first vegetables are ready for harvest. The students at the school will be involved in the growing process, helping to make sustainability an integral part of their studies. The produce grown outside will be incorporated into the meals served in the school cafeteria by Sodexo.
During the presentation on December 4, principals from 5 other area high schools were on hand to sample the food and learn more about the Freight Farms’ Leafy Green Machines. Perhaps more of the brightly painted containers will soon be appearing in surrounding communities, bringing fresh, locally grown food to school lunch rooms and teaching young people about sustainable living.
Photos by the author.