While the high firing temperature and quality of Campania International glazed and terracotta containers result in a durable and frost-resistant product, Campania International still recommend that they are stored in a frost-free covered area in winter. If left outside, water may accumulate in the container and freeze, causing the planter to crack and break. Planters that must be left outside should be covered to prevent water, snow, and ice from accumulating inside the planter.