There are a few small tasks worm farmers can do to ensure happy and healthy worms over the winter months. If you have an outdoor composter with red wigglers living in it, there are two options for keeping them alive in the coming cold weather. Obviously, you can bring them inside and start a vermicomposting bin, see http://www.naturesperfectplantfood.com/2011/11/15/easy-worm-bin-photo-essay/ or you can attempt to over-winter your worms outside. This is a bit tricky, the first thing to consider is the size of your compost. Worms can not freeze, your compost needs to be large enough that it won’t freeze straight through during the coldest times. Most bin designs will not be able to support your worms when the snow flies. A compost heap is the best bet for keeping worms alive outside till spring. Feeding the worms extra before the winter is helpful, any kind of composting will generate a certain amount of heat, hopefully preventing a total freeze up by providing a heat generating source however minute. Red composting worms can actually tolerate quite low temperatures, just above freezing will keep them alive but any further heating is worth going for. Insulating the heap with a straw or mulch covering is also a good plan. Be generous with this “blanket” try to make it at least 12 inches deep. Do not disturb the snow-pack, once the snow begins to pile up just leave it be. The snow pack provides a good deal of insulation just on its own. We have over wintered worms here in Winnipeg, but it’s not for the faint of heart and doesn’t always work depending on conditions. http://www.naturesperfectplantfood.com/2011/05/06/conclusive-proof-worms-survive-winter-in-winnipeg/ A good rule of thumb in this case is bigger is better. Good luck!