Once you have collected your herbs it is important to dry immediately what you do not use. When choosing a method to dry the herbs keep in mind that the environment needs to be dry. Moisture will lead to rot and mold, which destroys the herb. On the other hand if they are placed in the sun or a dehydrator with too much heat, the herb too, will be destroyed. So be mindful as you are drying of the heat and moisture levels. Check regularly and adjust the environment as needed. I've always dried mine in my basement on screens (living in Northern Utah) and have never had a problem. Find what works best for you and make adjustments as needed.
Preparing Your Herbs for Drying
I don’t bother washing or rinsing my herbs, just brush off what dirt you may see and pull out any other kind of debris, such as cobwebs, seed tufts or other plant material. In his book, Eat Dirt, Dr. Josh Axe says that consuming the dirt from the food we pick in our gardens (or forage in the wild) adds beneficial microbes to our intestinal flora. So, by not washing off our herbs we will also be strengthening our gut health, which equals a stronger immune system. When preparing roots, use a wash cloth to scrub the root, then chop into pieces before drying.
Simply lay your herbs on screens that have air flow on all sides. I use the large screens from an old dehydrator, you could also use a window screen or make something with screen or mesh material. I lay these on a laundry rack to get good air flow. Lay the herbs in single layers on the screen, although I lightly pile my herbs, just make sure you have air flow and check on them each day. I just lift and fluff them as needed. These need to be dried in a shady place outside (make sure it stays dry, you may need to bring in during the evening hours when there is more moisture) or inside your home, I dry mine in the basement. This method doesn't work for those that live in a humid area, it must be dry.
Just place your herbs on the dehydrator trays and place on the lowest setting, mine is 95 degrees. It depends on the herb for how long, just check on them every once in a while. Once they snap or crunch and all the moisture is out, they are done. Drying roots will need a higher temperature, somewhere between 100 and 145, depends on the thickness of the roots and the moisture content, chop roots before drying.
Storing Your Herbs
Once your herbs are crisp and snap when you break them its time to store them for future use. I keep my herbs in as whole of form as possible to preserve the medicinal properties longer. Crushing herbs will start the decomposition process, as will light and moisture. Glass is the best way to store your herbs, they keep out air and moisture because it doesn’t “breathe” like other containers and bags can. Re-use jars from food you buy at the grocery store, canning jars, specialty jars online or at a local craft store or big box store, etc. My friend’s family has an addiction to pickles, so she buys the Costco size pickles and gives me all the jars. For herbs I use a lot of through the summer months, like raspberry leaf, I store in 5 gallon storage buckets. Just make sure whatever container you use is air tight. Once “bottled” label your herbs and keep them in a dark, cool place. Many books and sources will tell you that dried herbs will only last a year and then discard them. I still have a jar of peppermint leaf I dried and stored three years ago and it is still as potent as the day it was stored. When it comes to dried herbs your “expiration date” depends on three factors; color, smell and taste. As long as your herb still has a vibrant color, smells aromatic and tastes potent, they are still good. Once they lose their color and potency, it is time to discard them.