According to Better Homes & Gardens, whole spices will stay fresh for up to 2 years. Ground spices will last for about 6 months. Yikes, time to clean out and replace some!! Something I did not know was to keep red colored spices in the refrigerator to maintain their color and flavor. I have always stored my spices in glass containers since plastic can be porous and lessen the flavor of the spices. Metal can be used for all except salt blends since metal can corrode the container.