If the plant is rated two zones lower than your current hardiness zone it is safe to stay in the pot outside all winter (example: plant hardiness zones are 3-7 and you live in zone 5 or above). If not, we recommend storing the container somewhere cold that does not go below freezing, like a garage, shed, etc, and wrapping the container in burlap or other material to further protect the roots. Plants that lose their leaves in the winter do not need sunlight during dormancy but evergreen plants do and would need to be placed near a window.