There are two types of end-of-season gardeners. There’s the I can’t wait to be done gardener. Then there’s the I want to squeeze out every last bit of goodness gardener. To all of those I can’t wait to be done types, don’t give up quite yet, there are some truly amazing things that you’ll be leaving behind if you don’t consider all the herbs to harvest after a freeze.
For certain medicinal herbs, the first hard frost peaks their medicinal properties, making it a good time to dig in and gather those roots. The cold stimulates and concentrates beneficial compounds within the plants, so don’t pack away your gardening tools just yet. When plants begin to go dormant at the end of the season, all the properties go into the root system. That’s when we go after them.
But the exact time and way you harvest them varies a little depending on the type of herb. So let’s explore how to get them out of your herb garden and onto your apothecary shelf.
Herbs to Harvest After a Freeze
Burdock (Arctium lappa)
Burdock root is a powerful herbal remedy traditionally used to support liver health, aid digestion, and promote healthy skin. Its roots become more potent after the first hard freeze when the plant begins storing energy in the form of nutrients. That’s when you’ll want to dig up the roots. It can be harvested throughout fall and early winter as long as the ground isn’t frozen solid. Obviously, trying to dig a frozen ground makes things way more complicated.
- How To Use: Burdock root is commonly used as a herbal tea or tincture. It can also be cooked as a root vegetable in soups and stir-fries.
- How To Harvest: After the first hard freeze, use a garden spade to loosen the soil around the plant. Be careful not to puncture or cut roots along the way. If you do not want Burdock to grow back the following year, be sure to get all of the roots when you gently pull them from the ground.
- Herbal Properties: Burdock is a highly detoxifying herb with anti-inflammatory and antioxidant properties. It’s especially known for supporting skin health and liver protection.
- Preserving Tip: Clean the roots with cool water, slice them into small pieces, and place them in a single layer in a dehydrator for drying. You can also chop the roots and freeze them in labeled freezer bags for later use.
Dandelion (Taraxacum officinale)
Dandelion roots are best harvested after the first frost. It is a whole plant herb—both the roots and the leaves are used for their health benefits. The roots are packed with inulin, a prebiotic fiber that supports gut health, and increases good probiotic load.
- How To Use: Dandelion root can be roasted to create a coffee substitute, tinctured fresh, or dried and added to tea blends.
- How To Harvest: After the first frost, dig deep a couple of inches away from the crown of the plant. Dandelion has a taproot and will return the following year if it is not completely harvested.
- Herbal Properties: Dandelion is a diuretic, liver tonic, and digestive aid. It supports detoxification and helps with digestive issues like bloating and indigestion.
- Preserving Tip: Wash the roots and chop before drying. Thick roots should be dried in a dehydrator.
Marshmallow (Althaea officinalis)
Marshmallow root is known for its soothing properties, especially when it comes to the digestive and respiratory systems. This herb is often harvested after a couple of frosts. The roots are packed with mucilage, making it a little slimy under the tough root skin.
- How to Use: Marshmallow root is typically used in teas, tinctures, and syrups to soothe sore throats, coughs, chest congestion, and gastrointestinal irritation.
- How To Harvest: After all of the foliage has died back, use a garden spade to dig in wide circles around the plant. Marshmallow roots like to reach, so use care when digging. Any root left behind will produce another plant the next year.
- Herbal Properties: Marshmallow is demulcent, meaning it forms a soothing layer over mucous membranes, which helps with dry coughs, ulcers, and irritated skin.
- Preserving Tip: Wash the roots, chop them into thin slices, and dry them in a dehydrator. Once fully dry, store them in airtight containers in a dark place for best results.
Ashwagandha (Withania somnifera)
Ashwagandha root is an adaptogen, helping the body manage stress and support immune function. The roots can be harvested after a freeze, particularly in climates where it’s grown as an annual. Ashwagandha is traditionally used in Ayurvedic medicine and is now popularly used to support anxiety and adrenal health. To learn more about Ashwagandha, read more here.
- How To Use: The root can be dried and ground into powder to capsulate, or used fresh and made into tinctures.
- How To Harvest: This herb has thinner wiry roots that spread out from the base of the plant. When harvesting, gently dig a wide circle around the plant and pull it up gently.
- Herbal Properties: Ashwagandha helps to balance stress hormones and support overall vitality, making it ideal for both physical and mental fatigue.
- Preserving Tip: This herb really shines as a tincture. To tap into its most potent properties. It can also be diced and air dried on a cookie sheet, rotating frequently until fully dried.
Valerian (Valeriana officinalis)
Valerian root is known for its sedative effects and is one of the most popular herbs for promoting restful sleep. Harvesting after the first hard frost results in more potent roots, as the plant’s energy is directed into the root system for winter survival. To learn more about Valerian, read more here.
- How to Use: Valerian root is commonly used in teas, tinctures, or capsules as a natural remedy for insomnia, anxiety, and muscle tension.
- How To Harvest: This herb has very thin and wiry roots. When harvesting, dig in a circle around the plant, loosening the soil well before pulling it out of the ground.
- Herbal Properties: Valerian root is a nervine herb with antispasmodic properties. It helps relax the central nervous system and muscles, promoting relaxation and restful sleep.
- Preserving Tip: After washing the root, chop it into small pieces and spread it in a single layer on a drying rack or in a dehydrator. Dry completely before storing in airtight containers in a cool, dark place.
Elecampane (Inula helenium)
The best time of year to harvest Elecampane is after a couple of frosts. It’s particularly useful for respiratory conditions like bronchitis and persistent coughs. These roots contain inulin that balances the moisture levels in the gut and the lungs. To learn more about Elecampane, read more here.
- How to Use: Elecampane root is best used in syrups, tinctures, and decoctions to support respiratory issues.
- How To Harvest: This herb has crazy roots. They are thick in spots, thin in others, and have a large mass under the crown of the plant. They also reach deeper and wider, making it tricky to completely harvest. Soil prep before planting elecampane will be very helpful at harvest. Make sure wherever you plant it has good tilth and is easy to work with.
- Herbal Properties: Elecampane is antimicrobial, demulcant, and expectorant, helping to clear the lungs of mucus and fight infections.
- Preserving Tip: Slice the roots thinly, dry them using a food dehydrator, and store them in a cool dry place for later use.
Ways To Preserve
Once you’ve harvested your herbs, it’s important to preserve them properly to retain their medicinal properties throughout the winter months. Here are a few options to help you find the right drying process to store and preserve herbs after a freeze:
Air Drying: Hang herbs in small bundles in a well-ventilated place. Secure the ends of them with rubber bands and let them dry out of direct sunlight with good air circulation until they are completely dry. This isn’t an ideal way to dry dense roots, but herbs with thinner roots, like Valerian, do just fine with this approach.
Freezing: When freezing herbs, chop the roots and freeze them in a labeled freezer bag. Another option is to freeze chopped herbs in ice cube trays with water or olive oil for quick use in recipes later. This technique works best for culinary herbs like turmeric and ginger. These herbs do have beneficial herbal properties, but they are more commonly used in culinary applications.
Freeze Drying: Freeze drying is the gold star of herb preservation. During the process of freeze drying, the herbal properties are locked in versus part of them evaporating in the dehydration process.
Food Dehydrator: A food dehydrator is a fast, effective way to dry roots for storage. Spread the roots in a single layer and dry them at a temperature no higher than 100ºF until they are completely dry.
Ways NOT To Preserve
Choosing the right preservation method is important, and so is knowing what you should NOT do…
- Oven Drying: There’s a lot of controversy over whether or not herbs should be oven dried. My personal experience and belief is unless you have an oven that has a high-quality dehydrate feature on it, this method is not the best option. Ovens do not have good air circulation in comparison to dehydrators, and it’s easy to over dry herbs in an oven.
- Sun Drying: Another popular approach to drying herbs is letting them dry in direct sunlight. As soon as herbs are harvested, they start to lose their potency. When herbs sit in direct sunlight, their properties start to break down. Properly dried herbs should be the same color they were when they were alive. If your herbs are faded and have lost their aromatic properties, they have also lost potency. Always dry out of direct sunlight.
- Long Drying Times: Even if you use the best drying method for the herb, you have to be mindful of drying times. Over-drying herbs can break down herbal properties as well, regardless of the method. Once your herbs are dry, store them.
Storing Your Herbs
Harvesting these leafy perennial fresh herbs for their roots is one of the most labor-intensive harvests of the season. So you’re going to want to take good care of your harvest. Make sure that whatever process you use to dry your herbs, dries them thoroughly. When you’re past that step, store them in glass jars with tight fitting lids or mylar.
The end of the growing season can be exhausting. Don’t forget that to harvest herbs after a freeze is the last hurrah of the year. It may be challenging, but, that last herb harvest will bless you with herbs that you can only harvest once a year, and will reap the benefits from all winter long.
If you want a close-up on how to harvest roots herbs, check out this YouTube video on harvesting Marshmallow roots.
