Great information on how to care for our spices and herbs.
How long can bottled spices be kept; what is the shelf life?
The good news is, spices do not spoil. The bad news is, they lose their strength. What is interesting is that a lot of cookbook writers tell you to purge your pantry once an herb or spice is about 6 months old. But the spice companies — among them behemoth McCormick and specialty spicer Penzeys — are not so reckless. They tell you to keep and use the spices as long as they appear to have flavor — and they trust you to be able to tell!
Stored in an airtight container, in a cool, dry place, spices retain their potency longer than you'd think — as long as 4 years for whole spices, 2 to 3 years for ground spices, and 1 to 3 years for leafy herbs, depending on the herb. Whole peppercorns, nutmegs and cinnamon sticks hold on to their flavor for ages. Particularly potent whole spices, such as cloves, cumin, and cardamom will also last for a long, long time.
Herbs lose their flavor faster than spices. Dried herbs that have no color and no or very little smell when crumbled in the palm of your hand are probably too old for practical use. Yet even if they don't look all that green anymore, but still have some oomph when crumbled in your hand, use them freely.
For ground spices, shake the jar, let it settle, and give a sniff. If there's essentially no smell, it should be tossed out. If the spices have a bit of fragrance left but are not as potent as you remember or think they should be, just use more in the recipe. Then you'll run out sooner and have a reason to start fresh with a new batch.
Of paramount importance in getting the most flavor and value out of your herbs and spices is to store them well — nowhere near the heat of the stove, nowhere near the humidity of the stove or dishwasher, nowhere bright and sunny. But don't get the idea that putting them in the freezer is ideal, either. Condensation will be a problem each time the bottle comes out of the freezer and is likely to introduce moisture in the spices. Similarly, don't ever shake herbs or spices out of the bottle directly into something you're cooking — that's the quickest way possible to steam and despoil your spices.