Harvesting & Drying Herbs

Growing your own medicinal or culinary herbs is intensely rewarding. There is a deep connection to the earth and your sustenance that you experience when you harvest your own plants for making into medicine, drying for teas, or using in the kitchen. In this article you will find a few tips on how to harvest your herbs, dry and store them for use throughout the year.

Each part of a plant has an ideal harvest time. Typically flowers should be harvested as they open, leaving the wilted ones on the plant to mature and form seeds. For especially aromatic flowers, such as roses, it is best to harvest them in the early morning before the hot sun is out. 

Leaves are at peak potency as the plants begin to form flower buds. Leaves, especially for culinary use, can be harvested at other stages in the plant lifecycle, but for medicinal potency they are many times more concentrated in constituents when the plants begin to flower.

Roots are always harvested in fall and winter when the plants have become dormant. Harvesting roots to medicine in the spring and summer when the plants are actively growing will reduce the medicinal potency of the harvest.

Tips on harvesting herbs:

• never harvest wet, dusty, or diseased leaves or flowers.
• use or dry herbs as soon as possible after harvesting
• do not leave them in your harvesting bag for long as they may begin to 'compost'
• harvest with clean sharp tools so that the plants are able to heal themselves more easily

Once you harvest and dry your own herbs and experience their vibrancy it will become hard to be satisfied with the dried herbs you find in the store. Unfortunately many commercially produced dried herbs are of poor quality and barely resemble the plants they came from. When dry, herbs should resemble the living plant material in all ways, especially smell, taste, and colour. For example:

• Red clover blossoms should be whole, bright pink or red and sweet smelling and tasting.
• Peppermint should retain its bright green colour and aromatics.
• Calendula flowers should be the same vibrant yellows and oranges you see in the fresh flowers growing in the field.

Herbs that are dried too slowly may mold or begin to decompose by enzymatic action. This can become an issue in damp climates, or if herbs are laid too thickly on the drying rack. Plants should be laid out to dry as soon as possible after harvesting. If they are left too long in the bag they quickly begin to compost.

If herbs are dried too quickly and with too much heat they may loose potency. Some resinous plants, such as rosemary or sage, may turn brown when dried too quickly due to rapid enzymatic activity. This may also happen to plants that have become bruised from handling. These herbs are best left to air dry slowly in a warm room.

Examples of places to dry herbs:

• A table tucked away in a shady corner of a bedroom or living room is a fine place to dry herbs. Lining the table with newspaper or brown paper bags will help with drying and help protect the table.
• Drying racks can be made from old window screens, just be aware that the materials used to make the screens were not necessarily intended as ‘food grade’ and may leach. You can make your own drying racks with recycled wood and wire mesh purchased at most hardware stores.
• For small quantities of herbs, dehydrators work great. Dry herbs on the lowest setting (around 30 degrees Celsius).
• Beer flats are free and abundant from your local liquor store and are a good space-saver for herb drying in small apartments.

Tips on drying herbs:

• Warm, shaded, well-ventilated areas are best.
• Optimal air temp 30-40 degrees Celsius.
• Direct sunlight rapidly reduces quality.

After drying, herbs will steadily begin to break down and lose quality over the months. Many herbs, especially those high in aromatics, will be considered of poor quality nutritionally and medicinally (and in flavour!) after only one year.

Examples of herbs that should be used within a year of harvest:

• Lemon Balm (Melissa officinalis)
• Red Clover (Trifolium pratense)
• Calendula (Calendula officinalis)
• Holy Basil (Ocimum sanctum)
• Mint (Mentha sp)

Once herbs are dried it is best to leave them as whole as possible until ready for use. Herbs that are broken down into small pieces have more surface area exposed to the elements that will cause them to lose potency. Avoid powdering your herbs in advance, as they will begin to deteriorate rapidly after they are powdered.

Tips on storing herbs:

• Leave herbs as whole leaves or flowers.
• Never powder your herbs until just before using.
• Most herbs, especially aromatic leaves and flowers, should be used up before a year after harvest as they will degrade rapidly. Roots and barks will last up to 3 years if stored properly.
• Once you are sure herbs are dry, store in a cool, dry, dark place in an air-tight container