I just ran across this video on a non-profit farm on 3 acres in Wisconsin & they can grow food 365 days a year. They use an intricate system of vertical growing, composting, and fish farming (using pumps from the fish water up to water the plants & then filter back down through plants and pebbles back to the fish.
I think this is wickedly cool and amazing, and a very interesting idea for cold climates since the compost does get hot while breaking down.
Mind you, I don’t have 3 acres (I think I have 1/8-1/4) and my dear husband would kill me if I put in a huge greenhouse. But I love the idea & would like to figure out how to do this on a smaller scale. What do you think?