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 grown for their leaves. These herbs should be harvested when their flower buds are just beginning 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 mid-summer and again in the fall.
Herbs should be harvested in the early morning, after the dew has evaporated but before the sun becomes 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 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 to 80 F), dark, well-ventilated location. 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 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 wooden blocks under the corners of the drying tray to insure good air circulation. Place a single layer of leaves or stems 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 oven door open and stir the herbs periodically until they are thoroughly dry.
Some herbs, such as dill, caraway, and coriander, are valued for their seeds. Harvest the seedheads just before they turn brown. Cut off the entire seedhead and place it in a paper bag. Then place the bags in a warm, dry location. After drying, shake the seeds loose in the bag. Remove any chaff by pouring the seeds from one container to another outdoors in a light wind. Additional information on harvesting and storing herbs can be found in Pm-1239 "Growing and Drying Herbs."
This article originally appeared in the July 27, 2001 issue, p. 96.
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