Wash and rinse the rosemary in a bucket or bowl of cold water. Rinse until the water is free of dirt or insects.
Cut the rosemary branches into smaller manageable pieces that will fit on the dehydrator trays.
Arrange the rosemary on the trays filling the tray. The rosemary may overlap slightly.
Dehydrate the rosemary at 95 to 105 F. degrees for approximately 8 to 14 hours. Check the rosemary frequently every couple of hours to check to see how dry it is.
Once dried strip the rosemary leaves from the branches. Pick out any pieces of stems.
Store the dried rosemary in an airtight container in a cool dark cabinet until needed.
When to harvest fresh rosemary: Fresh herbs like rosemary should be harvested early in the morning after the dew has dried but before the sun has reach its peak in the afternoon.
Use the freshest herbs: Dry fresh rosemary at its peak. The stems and leaves should not have any blemishes.
Flowering herbs: Harvest herbs before they begin to flower for the best flavor.
Dehydrating temperatures: The recommended drying times for fresh herbs vary from dehydrator manufacturers. Read the manual that came with the appliance. The round stackable Presto dehydrator used here recommends drying temperature at 95 F. degrees while the Excalibur Dehydrator recommends 105 F. degrees for drying herbs.
When is the dried rosemary done?: The rosemary is done when the leaves are dry and brittle to the touch.
How to store dried rosemary?: Dried herbs like rosemary should be stored in an airtight container in a dark cool cabinet to retain the flavor.
How to convert fresh herb to dried herb measurements: 1 teaspoon of dried rosemary is the equivalent of 1 tablespoon of fresh rosemary.