Strawberries are delicate plants--they can wither during an unexpected frost and rot on the vine in wet conditions. With proper planning, however, it is possible to grow strawberry plants through even the coldest of winters, and to reap a larger crop with each passing year.
Farmers in Manitoba don't plant the same variety of strawberry as farmers in Louisiana in the U.S. Find strawberry breeds that can survive in your "climate zone," a horticultural term used to help gardeners determine what can grow where. There are 11 zones in all--1 is the Arctic; 11 is the equator. Information on your climate zone is available through the U.S. Department of Agriculture. Information on the ideal climate zone for a breed of strawberries should be available through any reputable seed distributor or nursery.
According to the University of Illinois Agriculture Extension, strawberries are healthiest when they are appropriately watered and fertilized in preparation for winter. Lay down fertilizers (and insecticides, if you wish) in early fall, as this is when strawberry plants grow the buds that will become next year's fruit. As the cold weather approaches, water plants less. Do not water plants at all after the first frost.
In cold climates, even the heartiest strawberries need a little extra help. After the ground freezes in the late fall, cover your strawberry plants in a 3- to 4-inch layer of hay or mulch to protect them from the cold. Remove mulch in the spring after strawberry leaves turn yellow. Leave a thin layer of mulch on the ground to protect strawberries from the spring damp.