Moisture and exposure to light cause potatoes to spoil. To keep potatoes fresh for up to 2 weeks, loosely store them in a paper bag at room temperature. For long-term storage (up to 2-3 months), keep them in a cool, dry, dark place. Adding an apple to the mix will prevent potatoes from sprouting, while keeping onions nearby will actually cause them to sprout.
Store potatoes in a cool, dark place at room temperature. Keep away from onions and add an apple to avoid early sprouting.