Most herbs can be cut and used fresh throughout the growing season. They can also be harvested, dried, and stored for use during the winter months.
Many herbs, such as sage, rosemary and basil, are harvested for their leaves. These herbs should be gathered when the flowers are about to open. The oils in the leaves which give each herb its distinctive flavor and aroma are at their maximum levels at this stage of growth. Remove approximately 1/3 of the current year's growth on perennial herbs. Annual herbs can be cut back more severely. Make the cuts on annuals approximately 4 to 6 inches above the soil surface. The annuals can be cut at ground level when harvesting in the fall before the first frost. Most annual and perennial herbs can be harvested in midsummer and again in the fall.
Herbs should be harvested in the early morning, after the dew has evaporated and before the sun becomes too hot. After harvesting, rinse the herbs in cool water. Shake off excess water and place them on paper toweling to dry for a few minutes.
Air drying is the most popular method used to dry herbs. To dry whole branches or stems, gather 8 to 12 stems in a bunch. Tie the ends of the stems together and hang each bunch upside down in a warm (70-80 F), dry area. Don't dry the herbs in direct sunlight. The herbs should be dry in 2 to 4 weeks. When thoroughly dry, strip the leaves from the plants. Crush or crumble the leaves and store in airtight jars in a cool, dry place.
Another way to air dry herbs is to place them on a drying tray. A simple drying tray consists of fine mesh screen or cheesecloth attached to a wooden frame. A small window screen also works well. Place blocks under the corners of the drying tray to insure good air circulation. Place a single layer of leaves or branches on the drying surface and keep the herbs in a warm, dry area until they are thoroughly dry.
A gas or electric oven can also be used to dry herbs. To oven dry, spread a layer of leaves or stems on a cookie sheet or shallow baking pan. Place the herbs in a warm (up to 180 F) oven for 3 to 4 hours. Leave the door open and stir the herbs periodically until they are thoroughly dry.
Herbs can also be dried in a microwave oven. Place the herbs on a paper towel and cover with a second sheet. Set the microwave control on high and dry the herbs for 1-3 minutes. (This drying method requires experimentation to determine the exact drying time.) Then remove the herbs and let them cool.
Some herbs, such as dill, caraway and coriander, are valued for their seed. The seedheads should be harvested just before they turn brown so that the seeds don't fall off while cutting. Cut off the entire head and place in a paper bag. Then place the bags in a warm, dry area. After drying, shake the seeds loose into the bag. Remove any chaff by pouring from one container to another outside in a gentle wind. Additional information on harvesting and drying herbs can be found in Pm-1239, Growing and Drying Herbs, available at your local county extension office.
This article originally appeared in the July 15, 1992 issue, p. 122.
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