Fresh Herbs versus Dried Herbs
I am often asked questions regarding the use of fresh or dried herb, so here is the skinny. I try to use fresh herbs whenever possible. Fresh herbs are easy to grow at home outdoors or even indoors (by a window) in pots year round. Buying bunches of fresh herbs can get expensive, but most supermarkets have small staters in pots that you can easily replant so that you have an endless supply. If that doesn't work for you though, plan your meals in advance and buy fresh when possible- except for bay leaves (more on that later).
Fresh herbs should be stored either on the counter in a glass of cool water or in the fridge with the bottom of the stem wrapped in a damp paper towel. Stored properly, fresh cut herbs will last for up to a week, and "stemmy" herbs such as thyme or rosemary may last even longer.
In some instances however, buying fresh isn't practical or in the budget, so you have to make the best of dried herbs. Something to note, dried herbs don't always have the same flavor or aroma that fresh herbs do, and they do have an expiration date to keep an eye on.
When herbs are dried, their flavor usually becomes more concentrated, thus making them stronger in flavor; the exception here is bay leaves, which actually lose their flavor when dried (use half as many fresh bay leaves than you would dried). Because of their more intense flavor, a good rule of thumb is as follows:
1 tablespoon of chopped fresh herbs = 1 teaspoon of dried herbs
Another note to consider when cooking- fresh herbs are generally added near the end of the cooking process to maintain their vibrant color, delicate flavor and excellent aroma; whereas, dried herbs should be added earlier on in the cooking process to ensure that their flavor infuses into the dish and dried pieces are soften up by the heat.
Finally whether fresh or dried, don't forget to buy organic when possible. Pesticides and fertilizers easily cling to the delicate and absorbent leaves of the herbs, so although they aren't part of the eponymous "Dirty Dozen", they are should be.