Outdoor containers come in all sorts of materials, the most common of which is terra cotta, an unglazed, clay-based ceramic. Most terra cotta pots will crack if left out during a freeze, but some, crafted from a type of the clay made in Impruneta (Impruneta), Italy, are fired at a high enough temperature that they can stay outside all winter.
Planters made from cement are frost-resistant but also quite heavy. Use smaller, easy-to-move ones for succulents and alpine plants, which will thrive even in a diminutive pot. Select larger cement containers as permanent accents.
Improvements in molding and painting techniques have made lighter-weight fiberglass and plastic containers an aesthetically viable alternative to ones made from clay or cement. Whatever material you choose for a planter, make sure to place it on risers so it drains properly and doesn't stick to the ground.