You can dig up your dahlias as soon as the leaves begin to decay from a light frost. At this point cut the stems to the ground and lift the tubers from the soil and store in a cool, dry spot or you can try leaving the tubers in the ground but covering the soil on top of them with plastic and a mulch to keep the soil dry and above freezing. If you do store your dahlias in your garage do not place them in plastic bags. Use paper bags so they can breathe and replant when the weather warms in May. Keep growing, Marianne Binetti