Imagine raising vegetables in an abandoned, four-story manufacturing building. And doing it without soil.
An old building once used to manufacture plows for farm fields is being transformed into a dirtless vertical farm where fish and lettuce are grown in a symbiotic system.
The farm, in a part of the city that once was an industrial hub, potentially could produce the same amount of food as 40 acres of land without the use of pesticides or fertilizer, according to the entrepreneurs behind Natural Green Farms in Racine, Wis.
This particular method of growing food, using treated fish wastewater to grow lettuce, is nothing new. But it could be a cutting-edge venture if it turns an obsolete industrial building into a local model for a new industry that creates jobs and produces fresh food close to the people who would eat it.
In Japan, obsolete auto manufacturing buildings have been converted into food-growing factories, said Joe Heineman, who owns Natural Green Farms with his wife, Johanna Hearron-Heineman.
The Heinemans say they could produce 4 million heads of lettuce and 1 million pounds of fish a year if they expanded their model to fill all four floors of the building. So far, they're using portions of two floors -- about 10,000 square feet of the 200,000-square-foot building -- to grow 7,000 heads of lettuce a month, plus about 24,000 fish at different stages of maturity. They've been in the building, experimenting, for three years.
The couple is seeking investors and state assistance to expand. They figure it will cost $30 per square foot, or $6 million, to fill the building with fish and vegetables.
State Rep. Cory Mason (D-Racine) plans to bring a contingent from the state Department of Commerce and the Department of Agriculture, Trade and Consumer Protection to tour the farm in the River View District along the Root River.
"This is important to Racine in a number of ways," Mason said.
"It's an area that has been hit pretty hard by lost manufacturing jobs. An urban farm won't replace the 7,000 manufacturing jobs we lost, but if one business potentially can bring 50 to 60 jobs back to the core of Racine, that's a good start. The challenge for urban manufacturing communities is how you reinvent yourself for the 21st century."
Vertical farming receives a lot of attention these days, as cities talk about how to produce fresh food closer to large populations, using less energy and less land.
This vertical farm is different from one planned by Milwaukee urban farmer Will Allen, who has gained international attention for his innovative growing methods in tight spaces. Allen wants to build a five-story farm for $7 million to $10 million at Growing Power on Milwaukee's north side.
The Growing Power vertical farm would use nutrient-rich, composted soil in addition to fish wastewater to grow plants. It would produce 150 different vegetables and also serve as a training center for urban farmers.
The Natural Green Farms model is similar to plans on the drawing board in Chicago. The Chicago Sustainable Manufacturing Center is working with the Illinois Institute of Technology to develop a vertical farm called The Plant for a former meatpacking plant. It would raise tilapia and vegetables by recycling wastewater from fish tanks to nourish the plants.
Joe Heineman is a wholesaler of wicker baskets and candles, moonlighting as an urban farmer until he can increase the farm's capacity. Hearron-Heineman handles sales and tends the lettuce. Neither has a farming background. They researched the venture through the Internet and books.
Rick Olson is the sole investor. He owns the old JI Case building and two other industrial buildings in the neighborhood, and has a manufacturing background.
Electricity is a major expense for Natural Green Farms.
It costs 40 cents in electricity to produce one head of lettuce. That's $2,800 a month to grow 7,000 heads of Bibb lettuce they sell to wholesalers for $1.50 apiece. Ideally, they want to cut electricity costs in half. "Give us another year," Joe Heineman said.
They already grow lettuce at night, turning on grow lights when energy rates are lowest. Heineman is experimenting with different types of lighting to reduce costs. He also has considered installing windmills on the roof.
While they're innovating, Heineman said he hopes to grow a half-million pounds of tomatoes in a rooftop greenhouse.
"We're a green business," Heineman said. "Water is a scarce resource, and we use a tenth of what soil-based farms use."
The urban farm has attracted some international attention, thanks to the Internet.
Next week, the funding partners for a Guatemala-based system of orphanages plan to visit Natural Green Farms, said Joe Heineman. "They have 20 orphanages around the world and want to raise their own food."
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