It is mid-morning on March 6, and the thermometer has moved up about 10 degrees from its early morning reading of two degrees Fahrenheit. The record-breaking month of cold is still hanging on. Even so, when Christopher Hahn picks up an end of a row cover in his greenhouse, a surprising mass of bright green spinach and arugula greets us, happy and thriving in the ground bed where they have spent the winter. As the days have lengthened and the sun has become warmer, they’ve begun to grow again. Hahn says they will be ready for harvest in about a month.

The greenhouse, he explains, moves the Maine climate three zones south. “We’re in Washington, D.C.,” he says, as we stand in the largest of his three houses, basking in warmth close to 50 degrees while a northwest wind roars outside.

Last summer and fall, Hahn sold vegetables from his outdoor gardens and the greenhouses to restaurants – MaryEllenz and Solo Bistro in Bath, Sweet Leaves in Brunswick, the seasonal Lobster Shack in Phippsburg — and some Phippsburg families. Then, from early fall to early January, he picked 10 pounds of greens a week in the greenhouse, an assortment that included mustards, arugula, mache, radicchio and lettuce. He gives a lot of credit for his prolific harvest to the 22 yards of compost he obtained from Herb’s Compost in Clinton and the honeybees he keeps on the property.

Hahn is one of about 25 growers in Maine who are working on year round production of vegetables for local consumption. “Ideally,” he says, “I’d like to provide food for people on the Phippsburg peninsula. It’s critical that we reduce the amount of miles we travel and the amount of fossil fuel we consume to raise and obtain food.” He started last summer, and says he is still learning about the microclimate of his particular site, on the lower Phippsburg peninsula.

Hahn ate veggies from his greenhouse all winter, but because he didn’t manage to put in a large new crop in September and October to mature before the coldest weather appeared, he had to stop selling commercially January through March. Timing is everything in year-round production, he explained. If a crop of hardy greens like arugula or spinach matures by December, although it stops growing, it can be held for picking under row covers in the greenhouses. With large enough crops, a greenhouse grower can sell greens until the time he or she can raise a new crop, beginning in mid-February. Next fall, Hahn hopes to set this cycle in motion and sell commercially all year.

Energy conservation, sustainable practices and respect for limited natural resources have been important to Hahn for most of his life. Currently, he is on the board of two natural foods co-ops: Rising Tide in Damariscotta and an Arizona based mail order co-op, www.shopnatural.com. He grew up in Arizona and came East to attend Dartmouth College, but he left before completing his degree, because, he says, “It was the 60s, early 70s. It was time to be on the streets.”

In the early 70s, he visited Scott and Helen Nearing, authors of Living the Good Life: How to Live Sanely and Simply in a Troubled World, who had moved from Vermont to Harborside, Maine in 1953. Eliot Coleman had just settled in Harborside and was experimenting with four season growing techniques he had observed while traveling in Europe. Scott Nearing suggested that Hahn visit him. Coleman, who published Four Season Harvest in 1992 and more recently, Winter Harvest Manual, has been an inspiration and friend ever since.

For close to 20 years, Hahn moved around the country, working construction and learning about gardening. Then he returned to Arizona, intending to work on his father’s house for awhile. He stayed 18 years, settling in Prescott, where he supported himself with the building and home remodeling business, Houseworks, that he had started several years earlier. At the same time, he became well known in Prescott for the diversified gardens and orchard he created in his downtown yard.

When he returned to Maine in 2003, Hahn continued to work as a builder and started the greenhouse operation in 2006. His wood frame, plastic covered greenhouse was designed and delivered by Ledgewood Farm Greenhouse Frames of New Hampshire. The house has air vents at either end, and the sides can be rolled up, but plants do not receive rain. When necessary, Hahn waters with rainwater he collects from the roof in two 1,100 gallon tanks. Last summer, he never watered his outdoor beds, where he grows crops like broccoli, summer and winter squash and cucumbers.

Following Coleman’s model, which permits continuous use of greenhouses, Hahn designed his gardens and located the large greenhouse so it can be dragged by a tractor one full greenhouse length to fresh soil. This makes it possible for the soil he’s been using to recover and be replenished by rain and a green manure crop.

The demand for locally grown produce is exploding, fueled by a combination of concerns which include global warming, the safety of food we eat after several outbreaks due to contaminated greens, and along with this, fears about the security of our food supply; conserving our soil with sustainable farming practices and a desire to support small, local farms and restaurants and businesses rather than massive corporations that control huge organic farms.

“The restaurants I’m supplying would love to have greens all winter,” Hahn says. “And one of the chefs I know is connected to a lot of other chefs in Portland. He says they would want as much as they can get.”