Herb Harvest and Preservation

Growing herbs is easy! After all, these plants are wild by nature and have adapted to tolerate pests, diseases and even the neglect  of their two-legged caretakers who cultivate them for our health and pleasure.  But as we walk through our wild and cultivated gardens, the thought of how to capture and store as much of our plants healing and nourishing potential as possible can seem overwhelming.  

Fortunately it’s not as hard as one might imagine,

but before we get into herb preservation, let’s briefly discuss when and how to harvest.

Herbs, whether culinary, medicinal (or both as many are) should be harvested at the peak of potency for maximum benefit.  For most leaf crops such as those in the mint family (i.e lemon balm, nettles, basils, etc.) harvest at the early stages of flowering during dry weather using pruning shears, field knives or by stripping leaves off with bare hands. Blossoms such as calendula, chamomile and arnica should be harvested during dry sunny weather when flowers are fully open using your hands or a device such as a chamomile rake. Roots are best harvested when the plants are dormant (late fall through early spring) and the energy of the plant has gone from above ground growth back to its roots. Spading forks are best for digging roots as they don’t tend to cut lateral roots off as shovels can do.

To clean freshly harvested herbs, shake or lightly brush them to remove debris clinging to leaves. Washing leaves and blossom is not recommended as it can promote fungal contamination during drying. Leaves that are to be used fresh can be rinsed, lightly dried and refrigerated before use. Roots that are to be dehydrated or used fresh should be thoroughly washed with fresh water to remove soil and other debris before using.

Now that you have harvested your bounty at peak potency, it’s time to preserve all that goodness for future use. There are several ways to do this with dehydration being among the most common and oldest methods of preserving food and medicine .  One of the first things I learned from my teacher and Mother-in-law, Rosemary Gladstar was that the dried herbs we use to make our medicine should look, smell and taste as close as possible to the living versions of those plants before they were harvested.  It’s not difficult to retain that living vibrancy but it does require a thoughtful approach.

Ideally, herbs should be carefully dried in the dark with good air circulation, low humidity and temperatures not exceeding 110 degrees F so as not to volatize aromatic compounds. Roots and herbs with lower levels of aromatics can be dried using temps up to 120 F. Excessive exposure to the elements can promote oxidation which is detrimental to herb quality, so drying them as quickly as possible is recommended.  For home-scale drying, food dehydrators work great. You can also use open baskets or clean window screens placed horizontally on wooden clothes drying racks.  Bundles of herbs can be tied with string and hung overhead in an airy place but use care not to make the bundles too thick, which can slow drying. Herbs are dry when the leaves crumble when squeezed.  Stem removal is made easy by stripping leaves off by hand or rubbing the herbs over steel mesh to separate stems.

When stored in ideal conditions, dried roots can retain maximum quality for more than a year before their potency gradually declines. The quality of dried leaves and blossoms slowly begins to deteriorate after about 6 months. Highly aromatic herbs, such as tulsi and chamomile, are more susceptible to degradation than less-fragrant herbs, such as stinging nettles. Dried herbs should be promptly stored in airtight bags, jars or canisters, and then kept in the dark in a cool environment. One of the best home-scale dried herb storage options is to store herbs in airtight packaging in the freezer where the forces of degradation are slowed further by low temperatures.

Quick Use

Some people prefer to harvest and use their herbs fresh which is a great way to preserve potency. Fresh herbs can be refrigerated or frozen until use. Frozen herbs can be susceptible to freezer burn so consider vacuum-sealing which is a great option for long-term storage of dried herbs, as well.

When medicine making time comes around, fresh or dried herbs can be extracted in various solvents such as hot water, alcohol, vinegar or vegetable glycerin.  They can also be made into syrups, elixirs, salves, creams, liniments and a plethora of other various vehicles of  efficiently and enjoyably delivering the plant medicine to the people who need it. Enjoy the harvest!


Jeff Carpenter co-owns and operates Zack Woods Herb Farm. Descended from generations of Vermont farmers, he deepened his love and understanding of plants through an apprenticeship with Rosemary Gladstar, and as the co-owner of Sage Mountain Herb Products. Since those early days Jeff’s work as a farmer, agricultural consultant, author, educator, and researcher has focused on the cultivation, conservation, and marketing of medicinal herbs. Jeff recently co-authored the book The Organic Medicinal Herb Farmer, is the director of the International Herb Symposium and is the president of the Vermont Herb Growers Cooperative.  His passion for the green world is evident as he spends his days working in the fields and in the community.



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