I thought it would be interesting to learn what people living in very cold climates do to provide winter dormancy for VFTs. Where I live it gets a little too cold in the winter to leave them outside without protection, and I don't have a greenhouse. (Actually, it gets a lot cold.) I had to get creative, and a few years ago I came up with the idea of using a picnic cooler, which has worked out just fine. I have a piece of rigid clear plastic that I place over the top when I open the cooler on sunny days, which is adjusted through the use of some very high-tech sticks, like a cold frame. I put large square plastic containers in the bottom that are filled with several gallons of water to moderate the temperature at night when the cooler is closed, and the plants sit on top of those in their water trays. My VFTs have never frozen and have come through each winter just fine using this method.