At Eco Farm Day in Cornwall last February Eliot Coleman, the writer of the revolutionary book Four Season Harvest, was more like a rock star than an innovative organic vegetable grower. Young men with children on their shoulders queued up alongside older men with gnarled fingers to get his autograph.

Coleman has developed and documented an innovative program in which he grows crops year round on his Maine farm. But despite the popularity of him and his book we were unable to find anyone in eastern Ontario or east central Ontario who had adopted the system whole hog.

Coleman’s system has been clarified in what writer Deborah Bier calls the "four secrets of winter gardening."

First, create cover for the plants. Coleman places cold frames throughout the space within an unheated greenhouse. The theory is that the cold frames create a mini-climate where cold winter plants can grow throughout the year. That’s because the plants benefit from the influx of heat from the soil in the winter, working something like a heat pump. He achieved his best success with 10 ft. wide hoops within the greenhouse placed 2.5 feet apart and covered with a fabric.

Why haven’t farmers adopted the technology? Some enjoy the winter down time. Ross Balstone, of Osgoode, said he shied away from winter growing because "Any mistake is incredibly expensive."

Others have adopted some of the technology to extend the season. David McCreary, of Almonte, gets two extra weeks in the spring and fall by covering his crop with a white sheet that allows 90 per cent of the sun and precipitation to get through to the plants.

Maggie Loo, who operates a certified organic farm in Valley, PEI, has pretty well adopted Coleman’s system. The plants live under a floating cover and are fertilized with eel grass and rotting crabs. Others use manure and some table scraps depending on the fermentation for some heat.

The second secret is to choose hardy, cold weather plants and plants that can survive being frozen for a period of time. These include spinach, certain lettuces and a host of plants most people can’t pronounce. The plants will thaw during the day and start growing.

Maggie Loo says the temperature in her greenhouse was never below freezing in the air surrounding the plant until January when the outside temperature dropped to -15 degrees Centigrade. The temperature in the greenhouse dropped to -9 degrees, and beneath the floating row covers to -5 degrees.

The third secret? Plants should reach full maturity by the time there is only 10 hours of light daily. Plants won’t grow in fewer than 10 hours of daylight.

Finally, don’t water the plants in winter months.

There is more to Coleman’s innovation. He uses unheated greenhouses on rails, allowing him to move them from one location to another without being dismantled.