Here in Nova Scotia it is custom to winter in 2 deeps and I usually try to have them weigh approx 100lbs. They are still foraging on goldenrod and aster and some other wild flowers, but we could have a hard frost at any time. I have used bee cozys for the past several years. My hives always winter well, but I am wondering if any of you who live with long cold winters have any experience with 3 deeps rather than 2 and if it is a good idea? Most of my hives are strong with lots of bees and it can be a challenge to push them into 2 deeps, also I then worry about cluster space.