Usually, ladybugs hibernate in winter under leaves and tree barks. These birds feed of their own stored body fats during this period. Typically, ladybirds feed on aphids, scale insects and mealybugs, and are times used as insect control mechanisms.
1 Additional Answer
Ladybirds sleep under tree barks or under leaf litter. They hibernate in winter time often in large groups sometimes numbering thousands. In a more natural and quiet environment ladybirds can sleep through until March or April.