Suzanne's Mom's Blog

I liked this Marketplace radio story on Duluth, a very cold place where people are managing to grow lettuce and fish in the same water year-round.

Chris Julin reports, “Tony Beran is standing in the kitchen at the Lake Avenue Restaurant in Duluth, Minnesota, with a head of romaine lettuce in one hand and a clump of curly lettuce in the other.

” ‘They’re beautiful,’ he says.

“Beran’s the executive chef, and one thing he likes about these bunches of lettuce is how clean they are. ‘They’re grown aquaponically instead of in dirt,’ he says. ‘Which is wonderful in the kitchen. It’s less labor for us.’

“Another thing he likes about this lettuce is that it was grown just up the road. The restaurant features local ingredients, and Beran serves locally grown lettuce all year, which is a bit of a trick in a place like Duluth. Last winter, the temperature was below zero 23 days in a row.

“But it’s always warm in the greenhouse at Victus Farms, where Beran’s lettuce came from. It’s about an hour’s drive from Duluth in a little mining town called Silver Bay.

” ‘These are all our babies,’ says Mike Mageau, as he shows off his latest lettuce crop. [He’s a] professor of geography at the University of Minnesota Duluth. He runs a program in environment and sustainability, and this indoor farm is a research project. …

“Most of Mageau’s lettuce is floating. Each plant is stuck into a hole in an inch-and-a-half-thick sheet of polystyrene foam. The foam rafts float in pools in the greenhouse, and the lettuce roots dangle through the foam into the water.

“The fish live in a neighboring room. They’re tilapia, and they swim in nine round plastic tanks, each one about six feet tall. Waste from the fish gets pumped over to fertilize the plants in the greenhouse, and some of the pools in the greenhouse grow algae and duckweed that come back into this room to feed the fish.”

Learn more about this continuous loop and the cost to set one up at Marketplace. People commenting on the website say the concept isn’t new, but it was new to me.

Photo: Chris Julin
Mike Mageau, a professor at the University of Minnesota Duluth, grows lettuce year-round — indoors.