Preserving herbs by freezing or drying UMN Extension
Dry at temperatures of 110 – 130 degrees F. The pilot light on a gas oven or the oven light in an electric oven is enough heat for overnight drying. Dry for 3 to 4 hours. Stir herbs periodically until thoroughly dry. Indoor air-drying. Indoor air or room drying is an option for sturdy herbs like rosemary, sage, thyme and parsley.
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