Growing food with zero heating in Massachusetts winter

Jonathan Bates is better known for the food forest him and his colleague Eric Toensmeier planted on their 1/10th of an acre urban lot in Holyoke, Massachusetts. When I visited him in February, most of the lot and its 200 plant species were still covered with snow, but Jonathan showed me around their bio-shelter. Thanks to good insulation and thermal mass, the passive greenhouse maintains above freezing temperatures all winter, and allows them to grow food throughout the year.

For more information about how the greenhouse was built, visit permaculturegreenhouse.com