Did you know that when you add herbs to foods you cook in a slow cooker makes a difference? Dried herbs should be added at the beginning of the cooking time but most fresh herbs should be added near or at the end of cooking time. When fresh herbs are added at the beginning they will lose not only their color but also their flavor by the end of the long cooking time used in slow cookers. There is one exception to the fresh herb rule and that is rosemary. Rosemary can withstand the long hours of slow cooking and may be added in the beginning.