Drying and Preserving Herbs
by Matthew LeBannister

Throughout history many cultures have utilized herb gardens for medicinal and culinary purposes. The tradition of preserving herbs dates back as early as the great pharaohs of Egypt and the first Chinese emperors. Archaeologists even found a small satchel containing dried medicinal herbs on the “Ice Mummy” recovered in the Italian Alps.

Herb gardens are small and easy to tend to. This is leading to a resurgence of gardeners willing to grow, harvest and preserve their own herbs. Most of us prefer to consume herbs fresh, since the potency of the plant diminishes when it is dried for preservation. By drying the herbs, they become impervious to molds, mildews, disease and other problems. This also means that the herbs will be available for consumption or application during seasons when it is not available fresh.

The only way to preserve herbs is to remove all moisture from the plant. There are three main methods for drying herbs effectively. Oven drying, frame drying and natural drying are the most common techniques. Each technique has its pros and cons and some are preferable to particular herbs. Which method is used depends on the individual grower, but the desired outcome is the same: to preserve and store the herbs for use at another time.

The first method of herb preservation to be explored is oven drying. Oven drying takes about an hour and is the quickest method of drying. This artificial drying technique is more often used to dry herbs that contain a lot of moisture such as basil or mint.

To properly oven dry your herbs place them uniformly on a baking tray. Make sure that the herbs are not touching each other. Cover the tray with tin foil leaving the corners uncovered to allow moisture to escape. Place the tray in an oven preheated to 150°F. Flip the herbs every 15 minutes until they are evenly dried.

There are disadvantages to oven drying your herbs; for instance, they can be easily over-cooked or burnt. If this happens, the herbs retain zero per cent of their original potency, making them worthless. Furthermore, oven drying your herbs means they will retain less of their original potency than herbs dried naturally. When herbs are being preserved for medicinal purposes, this loss of potency might be a good reason to try one of the following two drying techniques.

The next two herb drying techniques are considered natural drying because they each use a different method to dry the herbs in the open air. The first method is quite easy, because it simply involves hanging the entire plant upside down and allowing the surrounding environment to remove the moisture from the herbs. An easy way to do this is to wrap an elastic band around the bottom of the plant. A paper clip can then have one end hooked into the elastic band and the other end can be used to hang the plant from a clothes hanger or string. Hanging the plant upside down allows essential oils to flow from the stems into the leaves or flowers that one wishes to keep. While easy, this method is the slowest process of drying herbs. This natural process is most often used on herbs that do not contain a significant amount of moisture, such as dill and rosemary. Some gardeners prefer to hang dry their herbs outside. If you choose to do this make sure that there is plenty of sun. Herbs that are dried outside will encounter such risks as exposure to mold and other pathogens. It is safer to dry herbs indoors in a room with a dehumidifier or a room with excellent airflow. If a room like this is available, drying in the dark can be safe and effective. Drying culinary herbs in the dark can preserve the taste and smells, whereas drying the herbs in direct sun can often alter the taste of some herbs.

Similarly to hang drying, frame drying is another method that involves natural open-air, but it utilizes a different apparatus to dry herbs. Instead of hanging the plant upside down, the herbs should be spread evenly across the frame. In order to provide enough room so that the herbs do not touch each other, the frame should be at least three to four square feet. Line the bottom of the frame with tinfoil, keeping the reflective side facing up. Once the herbs are placed uniformly inside the frame, the glass lid should be fixed in place. The frame should not be airtight, to allow the moisture to escape. Now the frame is ready to be placed outside in a sunny area. The sun will penetrate the glass and reach the herbs. The sun will also hit the reflective side of the tinfoil and the grass will keep the heat of the sun inside the frame, making it more effective at drying herbs than simply hanging them outdoors. The herbs should be flipped once a day to ensure that they dry evenly.

The main advantage to using either of these natural open-air herb drying techniques is that there is no chance of over-drying or burning. Also, the final product will retain more of its original potency that herbs dried in an oven.
However, the disadvantage of these methods is that there is a risk of under-drying. This can allow mold to grow on the herbs, and ruin the final product as a result. These open-air drying techniques are, of course, slower than oven drying, for they can take one to six weeks to fully dry the herbs.

Now that your herbs have been properly dried they need to be stored properly. The three most popular herb storage techniques are sealed plastic bags, plastic containers or glass mason jars.

Herbs are good for us and many are delicious. Herb gardens are springing up in backyards, balconies and indoor grow rooms. With the precious knowledge of how to dry and preserve herbs properly, there is no reason to ever go without those homegrown chives on your baked potato or the garden basil in your favorite pasta sauce.

Matt LeBannister

Matt LeBannister developed a green thumb as a child, having been born into a family of experienced gardeners. During his career, he has managed a hydroponic retail store and represented leading companies at the Indoor Gardening Expos as a marketer. Matt has been writing articles for Maximum Yield since 2007.