Rosemary is an excellent herb for drying but unlike other members of the mint family like basil, it gets hard and woody when its moisture is removed so you won’t be able to crumble dry rosemary leaves with your fingers. If you are drying whole sprigs, the leaves will fall off the stem easily when they are fully dried. Here are some of the best ways to dry rosemary for the best flavor:
In the oven
One of the simplest ways to dry rosemary is to use the oven on its lowest setting to remove most of the herb’s moisture and thus help to preserve it.
Start by rinsing your fresh rosemary and then drying it off with a paper towel or cloth. Place a piece of parchment paper on a cookie sheet and spread rosemary sprigs in a single layer. Preheat the oven to its lowest temperature setting (usually around 200 degrees Fahrenheit) and put the rosemary in for about two hours.
If the needles are not brittle and falling off the stem at the end of two hours, you can let it go for a few more minutes or turn the heat off and let the rosemary sit in the warm oven for an hour or longer.
In the microwave
Rosemary dries quickly in the microwave. When you use this method correctly, you can have perfectly dried rosemary in a matter of minutes.
Remove water from your rosemary sprigs with a paper towel or let it air dry for a few hours. While this is an important step regardless of the method you intend to use to dry the herb, it is especially important with the microwave. Moist rosemary will steam in the microwave rather than dry out. Start by microwaving the herb for about 3 minutes then check it to see if the needles are brittle and break easily. If they aren’t, microwave again in 30–second bursts until they are.
A quick warning about drying herbs in the microwave: this appliance can scorch your herbs if you are not careful.
The oldest way to dry herbs is also the cheapest since it doesn’t require the use of electricity or gas. You can simply hang sprigs of fresh rosemary to dry them out. First, you will want to rinse the rosemary then pat the sprigs dry with a paper towel or dry cloth. Next, you will make small bundles that you tie at the bases with twine. The ideal location for drying rosemary will be in a location with low humidity and good air circulation. Some people prefer attics for this purpose. You can also try spaces on the outside of your home like a porch.
The downside of air-drying rosemary is that it will take a while for the herb to dry out fully. It depends on the humidity of the air around the rosemary and how well it is circulating but it will usually take at least two weeks and in many cases, about three weeks or longer.
In a food dehydrator
A food dehydrator is arguably the most reliable option for drying rosemary. It doesn’t need good air circulation to be effective and it won’t scorch the leaves. It was designed to dry herbs and other foods evenly and thoroughly. You should make sure that your leaves don’t have any surface moisture by patting them with a paper towel, or they will steam until the leaves dry off. Follow your appliance’s instructions for drying herbs.