Summer cooking is the best cooking with the availability of fresh herbs from your garden. Nothing quite compares to their flavor during peak season. However, with a little bit of planning, you can come pretty close. All you need is heat, low humidity and good air circulation to dry and preserve the flavors in their leaves, stems and seeds.
Harvesting herbs
The best time to harvest herbs for drying is before they start flowering. Once their flowers have opened they tend to taste more bitter.
How to harvest herbs
1. Harvest mature herbs on a sunny day in mid-morning after the dew has evaporated to capture more of their essential oils.
2. Cut the stems just above a leaf or pair of leaves, leaving 4-6 inches of stem for continued growth.
3. To harvest seeds, you’ll have to wait for the plant to fully mature.
Preparing herbs to be dried
1. Remove bruised, soiled or imperfect leaves and stems.
2. Check for insects, especially on seeds.
3. Rinse stems in cold water.
4. Shake to remove excess moisture.
5. Pat dry with a paper towel or remove moisture with a salad spinner.
How to dry herbs
When choosing a drying method you need to consider whether or not the variety is tender. Less tender herbs — sage, thyme and winter savory — can be tied into small bundles and air-dried. Tender-leaf herbs that have a high moisture content — basil, tarragon and lemon balm — will mold if they are not dried quickly.
Air drying (for less tender herbs). The success of air drying herbs relies on good air circulation and low humidity. Chose a location free of humidity and dust. The follow these steps:
Clusters
1. Tie the stems of herbs into a small cluster. Using a rubber band is recommended as it will tighten as the stems shrink and dry out.
2. Cover herbs with a paper bag punched with holes to keep the dust off and allow air to circulate. If you’re drying seedy herbs, make sure the bottom of the bag is left intact to catch the falling seeds.
3. Hang herb clusters in a dry area with good circulation.
Small-leaved herbs
1. Lay out on a fine stainless steel or food-safe plastic screen or paper towels to air-dry.
2. Once dried, strip the leaves from the stem to store.
Large-leaved herbs
1. Remove leaves and lay on stainless steel or food-safe plastic screens or paper towels without allowing the leaves to touch.
2. Layer up to five layers of herbs and paper towels.
3. Change paper towels as needed until herb leaves are dried.
Seed harvesting. Some herbs are desired for their flavorful seeds. A few examples are dill, caraway, mustard and fennel. As mentioned above, you should wait to harvest these herbs until they are fully mature. Once they’ve reached maturity, follow these steps:
1. Cut flower stalks or pull entire plant from the ground.
2. Hang upside down.
3. Shake seeds out when dry.
4. Examine seeds for insects.
5. Remove husks from seeds by rubbing them between your hands and blowing away the chaff.
6. Check for insects again and treat dried seeds.
Using a dehydrator. You may try this method for tender herbs that need to be dried quickly. Follow these steps:
1. Set temperature between 95 and 110 F.
2. Place stems on drying trays so they do not touch.
3. Dry larger leaves separately.
Pro tip: Do not dry herbs with fruits or vegetables because the flavors may mix and the moisture contents are different.
Using a microwave. This is another option for tender herbs. Parsley, basil and celery leaves dry well using this method.
1. Arrange washed and dried herbs one layer thick between microwave-safe paper towels.
2. The length of time will depend on the number of herbs and the power level of the microwave oven but a good baseline is microwaving on high for 2 to 3 minutes per cup. Start off with one minute, mixing after every 30 seconds. Then continue this process, checking for dryness.
3. Once dry, remove from microwave and cool.
4. Rub between paper towels to crumble.
5. Repeat with remaining herbs.
Pro tip: A microwave oven with a wattage rating of 1,000 or higher may heat too fast to use this method. However, even with lower watt microwaves, it’s important to keep an eye on the paper towels during this process.
Oven and sun drying. Oven drying isn’t recommended because even the lowest temperature destroys the flavor, oils and color of the herbs. If you decide to attempt this method your oven should not be set above 180 F and the herbs should be dried for 3 to 4 hours with the door open. Sun drying is only recommended in climates with low humidity levels.
Preparing herbs for storage
Testing for dryness. Before storing your herbs, you want to make sure they are completely dry to prevent mold growth. When herbs are dry their leaves will crumble easily between your fingers.
Treating air-dried seeds and herbs. Herbs and seeds that have been air-dried should be treated before storage to destroy any insects or insect eggs. You can either heat them to 160 F for 30 minutes, which may reduce flavor, or you can freeze them at 0 F or lower for at least 48 hours.
Storing dried herbs
To properly store herbs, you want to make sure they aren’t exposed to air, heat or light.
Storage containers. Use airtight and vapor-proof containers to prevent herbs from absorbing moisture from the air and other foods from absorbing the fragrance of the herbs.
Storage location. Store in a cool, dry, dark cupboard or drawer away from any stoves or sinks.
Whole v. crushed herbs. You can store your herbs either way; however, who herbs hold their oils and retain their flavor longer.
When to throw out. Most dried herbs keep well for up to a year. You can judge their strength by their smell.