How to Dry Herbs: Air, Dehydrator, Oven or Microwave
Rinse and thoroughly dry the herbs, then hang sturdy ones such as rosemary, sage and thyme in small bundles somewhere warm, dry and airy. Dry tender, juicy herbs such as basil, mint and lemon balm quickly, in a dehydrator at 35–43°C (95–110°F) or in a holed paper bag, because they go mouldy if they dry slowly.
They are ready when the leaves crumble and the stems snap. Store them whole in airtight jars somewhere cool, dry and dark, and they keep their flavour for up to about a year. Only dry wild plants you can identify for certain.
What you need
- Small bunches of 5–10 stems Sturdy, low-moisture herbs (rosemary, sage, thyme, savory, parsley)The easiest to air-dry in hanging bundles
- Small bunches, or loose leaves Tender, high-moisture herbs: mint, peppermint, basil, oreganoDry these quickly: a dehydrator, a holed paper bag or leaf by leaf
- Small bunches, or loose leaves Lemon balmA high-moisture herb; treat it like mint
- Flower heads, picked without stalks Chamomile flowersSpread the heads in a single layer on a screen or tray
- Young tops, stripped from the stems Nettle leavesWear gloves to pick and strip them
- Flower stems or petals Lavender or calendula flowersHang lavender in bundles; spread calendula petals on a tray
Equipment
- Scissors or secateurs
- Salad spinner or clean tea towels
- Rubber bands or string
- Paper bags (for the bag method)
- Food dehydrator, or an oven or microwave
- Paper towels or a fine mesh screen
- Airtight glass jars with lids
Method
Pick at the right time
Harvest most herbs just before the flowers open, when the flavour is strongest. Pick in the morning once the dew has dried, cut stems just above a pair of leaves, and avoid bruising the leaves. Don't leave cut herbs lying in the sun.1,2
Rinse and dry them well
Discard bruised, soiled or damaged leaves and stems, and check for insects. Rinse the herbs in cool water, shake them gently, then pat dry with paper towels or use a salad spinner. Get off as much water as you can before you start drying.1,2
Match the method to the herb
Sturdy herbs such as rosemary, sage, thyme, savory and parsley are the easiest to dry and can be air-dried in bundles. Tender herbs such as basil, oregano, tarragon, lemon balm and the mints hold more water and will go mouldy if they are not dried quickly, so use a dehydrator, a paper bag or the leaf-by-leaf method.1,2
Air-dry sturdy herbs in bundles
Tie small bunches with a rubber band, which tightens as the stems shrink, and hang them upside down somewhere dry with good air movement, away from the sink, kettle, stove and dishwasher. Indoors gives better colour and flavour than outdoors, and sun drying is not recommended.
How long it takes depends on the herb and the humidity, often one to two weeks; check them every few days.1,2
Use a paper bag for tender herbs and seeds
Punch or tear holes in the sides of a paper bag, put a small bunch inside with the stems at the top, and close the bag round the stems with a rubber band. Hang it where air circulates. Keep the bunch small, as large amounts go mouldy. Any leaves or seeds that drop are caught in the bag, which also keeps dust off.1,2
Or dry leaf by leaf
For mint, sage or bay, pull off the best leaves and lay them on a paper towel without touching, cover with another towel and add another layer; up to five layers can dry at once. Leave them somewhere airy, changing damp towels, or overnight in a switched-off oven with only the light on. This works better than hanging in humid weather.1,2
Dehydrator: low and slow
Set the dehydrator to 35–43°C (95–110°F); the US home-preservation centre gives up to 46°C (115°F), and up to 52°C (125°F) in very humid areas. Lay the herbs in a single layer so they don't touch. They usually take 1 to 4 hours, so check them regularly. Don't dry herbs alongside fruit or vegetables, as flavours and moisture mix.1,2
Oven: only as a last resort
Even the lowest oven setting drives off much of the flavour, oil and colour, so extension services generally advise against it. If you must, use the lowest setting, no higher than 82°C (180°F), leave the door open, and dry for 3 to 4 hours, checking often.2
Microwave: small amounts, watched
Lay washed, dried leaves one layer thick between microwave-safe paper towels. Heat on high for 1 minute, then in 30-second bursts, mixing and checking each time; a cupful usually takes 2 to 3 minutes in all. Microwaves of 1,000 watts or more may heat too fast. Stay with it: with too few herbs, the paper towels can catch fire.2
Check they are fully dry
Herbs are ready when the leaves are crisp and crumble easily between your fingers and the stems snap rather than bend. If anything still feels soft or leathery, give it longer: herbs that are not completely dry can go mouldy in the jar.1,2
Treat air-dried herbs and seeds for insects
Penn State Extension advises treating air-dried herbs and seeds to kill any insects or eggs: heat them at 71°C (160°F) for 30 minutes, or freeze them at 0°F (about −18°C) or colder for at least 48 hours. Heat costs some flavour and kills seeds you want to sow.2
Store them airtight, cool and dark
Strip the leaves from the stems and store them whole if you can, as whole leaves keep their oils and flavour longer; crumble them as you use them. Pack them into airtight glass jars and keep them in a cool, dry, dark cupboard, not by the stove or on a windowsill. Label each jar with the herb and the date.1,2
Safety
- Rinse herbs in cool water and throw out any bruised, soiled or damaged leaves before you dry them1,2
- Dry herbs until crisp before jarring them, as damp leaves go mouldy in storage. Throw out any jar that looks mouldy or smells musty2
- Never leave the microwave: with too few herbs, the paper towels can catch fire2
- Only dry wild plants you can identify for certain. People have died after mistaking hemlock for wild carrot, and pennyroyal, a mint, is poisonous3
- Avoid taking jars in and out of the fridge or freezer: condensation can form inside and spoil the herbs2
Variations
Chamomile heads and calendula petals dry best spread in a single layer on a mesh screen or paper-lined tray, turned once or twice. Lavender can be hung in bundles like rosemary.
Leave dill, fennel or caraway seed heads on the plant until the seeds are mature, then hang the heads upside down inside a paper bag and shake the seeds out once dry. Rub off the husks between your palms and blow away the chaff.
Once everything is dry, mix your own blends, such as thyme, rosemary and sage for roasting, or peppermint and lemon balm for tea. Keep a jar of each herb on its own too, so you can adjust the mix.
Does it actually work?
Drying works well for keeping herbs, but it changes them. Dried herbs are about three to four times stronger than fresh by volume, so use a quarter to a third as much, roughly 1 teaspoon dried for 1 tablespoon fresh. Heat drives off flavour, which is why low temperatures and quick drying give the best results.
Most dried herbs keep their flavour for up to a year; after that they are safe if dry and mould-free, but weaker, so judge them by their smell. Drying does not turn a herb into a remedy: for what peppermint, chamomile, lemon balm or nettle can and can't do, see their ingredient entries, linked above.1,2
Evidence ratings for what goes in: Peppermint, Lemon Balm, Chamomile, Nettle, Lavender.
Questions people ask
What temperature should I dry herbs at?
In a dehydrator, 35–43°C (95–110°F) is the usual range; very humid places may need up to 52°C (125°F). In an oven, use the lowest setting, no higher than 82°C (180°F), with the door open, but expect to lose more flavour and colour.
How long do herbs take to dry?
In a dehydrator, usually 1 to 4 hours. Hanging bundles take much longer, often one to two weeks, depending on the herb and how dry the air is. Go by feel rather than the clock: leaves should crumble and stems should snap.
How long do dried herbs last?
Most keep their flavour for up to about a year in airtight jars somewhere cool, dry and dark. They don't suddenly go off, but they fade, so sniff them: if a crushed leaf has little smell, it will add little flavour. Whole leaves last longer than crumbled.
Should I wash herbs before drying them?
Yes. Rinse them in cool water, shake them, then pat them dry or use a salad spinner, and throw out bruised or soiled leaves. The key is to get the surface water off before drying, so the herbs dry quickly and don't go mouldy.
How much dried herb do I use instead of fresh?
About a third as much: 1 teaspoon of dried herb for 1 tablespoon of fresh, or a quarter teaspoon if it is ground to a powder. Dried herbs are roughly three to four times stronger by volume.
Sources (3)
- University extension National Center for Home Food Preservation, University of Georgia. Herbs (drying). From So Easy to Preserve, 6th ed., 2014.
- University extension Zepp M, Hirneisen A, LaBorde L. Let's Preserve: Drying Herbs. Penn State Extension. Updated 2023.
- Poison centre Poison Control (National Capital Poison Center). Poisonous and non-poisonous plants: An illustrated list.
Educational only. Patch-test anything new on your skin, and stop if it irritates.
Reader notes
Experiences and questions from readers, read by an editor before they appear. They are personal accounts, not evidence, and are not medical advice.