Although it is usually just the leaves of the fresh cilantro plant that are used, the stems and roots are edible as well. Fresh cilantro is usually sold in bunches alongside fresh parsley. Choose cilantro with bright, evenly-colored green leaves, showing no sign of yellowing or wilting.
How to Store Cilantro
As soon as you arrive home with fresh cilantro, place the stems (with roots intact if attached) in a glass of water and cover the the top loosely with a plastic bag. Refrigerate. Snip off leaves as you need them and re-cover. The water should be changed every 2 to 3 days. Do not wash the herb until you are ready to use it since excess moisture will turn the leaves to green slime during storage. Depending on its treatment at the market, it should last up to a week in the refrigerator.
To freeze, place a small amount dry cilantro leaves in a single layer on a cookie sheet. When frozen, gather into a zip-top bag, returning to the freezer immediately. Use within 6 months. Do not thaw before using.
Cilantro may also be dried in the same manner as parsley, however, its flavor will be greatly diminished. Drying is neither recommended nor worth your time. Dried cilantro is available in most markets, should you have the need.
Coriander Selection and Storage
The seeds of the cilantro plant are known as coriander in the Americas. As with any spice, coriander seeds should be kept in a sealed container away from light and heat. The flavor will begin to diminish after about 6 months. Use within 1 year.