I don't know if you're interested in advice/whatever, but I've been doing a buttload of reading about compost recently, having just bought some new compost bins. There was a thread I read about compost heat, saying that in theory you should be able to keep a compost heap "alive" through most winters if it has enough nitrogen ("greens"). My reading suggested that more nitrogen will make compost faster, hotter, and smellier… if you have way too much then the smelliness will be overwhelming and unpleasant, hence the addition of browns to cool it down a little. But for a cold winter, maybe you could up the greens a bit ahead of time, and try and make it nice and hot/fast as the weather cools down?

I also just bought a compost aerator (corkscrew style, a bit like this one) and I imagine something like that might help prevent the whole heap freezing solid. But I can't say I'd relish the idea of trudging through the snow down to the back of the yard to wrestle with the compost in the dead of a really cold winter. I guess aerating early on and getting the layers nicely mixed might mean it doesn't freeze so solid. So, eh, not sure whether that's a helpful suggestion or not. Just thought I'd put it out there.

Replying in this really awkward way to Skud, but advice is never unwelcome. I think the problem was just the tight layering though. The proportion seemed fine in all other ways, no smell, the compost layers finished okay. If you've ever seen a manure pile full of straw, you know how hard it is to get it to break down. I think it cooled down in winter as the rest of it finished, froze and stayed frozen because the straw insulated it.

I might look into an aerator though. We never turned the pile in the fall because it rained all of October-climate change sure is fun.

Comments you can't reply to are really awkward beasts.