How to Dry Mint: Dehydrator, Air, Oven and Microwave

Want a jar of your own dried mint for tea or cooking? The one rule: dry it fast. Mint is one of the tender, high-moisture herbs that mold if they don’t dry quickly, and the University of Wisconsin says a dehydrator is the best tool for them.¹ Air-drying works too, with small bunches or single leaves in dry air. One study even found that drying made spearmint smell mintier, and that gentle heat or plain room air kept more of its aroma compounds than freeze-drying.²

At a glance

Method	Settings from named sources	Time	Notes
Dehydrator	95–115°F, up to 125°F where humid³; Penn State says 95–110°F⁴	1–4 hours³	Best for high-moisture herbs like mint¹
Air-drying, bagged bunches	Small bunches inside a paper bag with vent holes, where air circulates	Usually 5–10 days⁵	Works best when humidity is low
Air-drying, single leaves	Leaves on paper towels on a tray	Until crisp	Suits mint especially
Oven	Lowest setting, not above 180°F, door open⁴	3–4 hours⁴	Or overnight with only the oven light on³
Microwave	On high, from 30 seconds to 3 minutes depending on the source (table below)	Minutes	Small batches only; paper towels can catch fire⁴
Sun	Not recommended		Costs color and flavor

Before you start

The extension guides agree on timing. Most herbs are best harvested for drying just before the flowers first open, picked early in the morning once the dew has dried. Oregon State adds that cut herbs shouldn’t lie in the sun or sit around after harvest.

Rinse the stems in cool water and shake off the excess, then pat off all the visible water with towels or paper towels. You’ll often read that rinsing rids herbs of pathogens. The extension guides call it cleaning and make no such claim.

Dehydrator

This is the one to reach for with mint. The Wisconsin guide says a dehydrator is best for high-moisture herbs. NCHFP says to preheat with the thermostat at 95–115°F, going as high as 125°F where it’s humid, and to expect 1–4 hours, checking now and then.³ Penn State’s range tops out lower, at 110°F.⁴ Strip the leaves or lay whole sprigs in a single layer, and start checking at the one-hour mark.

Air-drying

You can air-dry mint, but it’s less forgiving than sturdy herbs like rosemary. Moist herbs air-dry best when the humidity is low, Wisconsin says. Tie them in smaller bunches, check the bunches for mold now and then, and throw out any that show it.¹

Bagged bunches. Oregon State’s method for tender herbs: tie small bunches (big ones will mold), hang them inside a paper bag with vent holes cut in the top and sides, close the top with a rubber band, and put the bag where air moves through it. It usually takes 5–10 days.⁵ Keep drying herbs away from the sink, stove and dishwasher, where the air is moist. NCHFP says drying indoors usually gives better color and flavor than drying outdoors.³

Single leaves. NCHFP calls drying the leaves separately “especially nice” for mint,³ and Oregon State says spreading leaves on paper towels on a tray works well for it. A window screen or a frame covered in fine mesh, propped on blocks so air gets underneath, does the same job. Keep to a single layer in a warm, dry room.

Oven

An oven only works if it can run cool. Penn State’s method is the lowest temperature, not above 180°F, for 3 to 4 hours with the door open.⁴ The Wisconsin guide gives the same numbers, with the herbs in a single layer and stirred now and then. Drying herbs too hot can cost you flavor, Oregon State warns. You’ll often see quick oven sessions of 15 to 30 minutes at 180 to 200°F suggested for mint. None of the extension guides we checked recommends one.

The cool-oven method works well for mint leaves. Lay leaves on a paper towel so they don’t touch, cover with another towel and another layer of leaves, and repeat for up to five layers. Leave them overnight in an oven warmed only by the light of an electric oven or the pilot light of a gas one.³

Microwave

The microwave is fast, and it’s for small amounts only. The guides don’t agree on timing:

Source	Amount	Time on high	Method
Penn State⁴	Per cup	2–3 minutes	Start with 1 minute, mix every 30 seconds, keep checking
University of Tennessee⁶	Per cup	2–3 minutes	Start with 1 minute, mix every 30 seconds
Oregon State⁵	1 cup (never more than 1–2 cups)	1–2 minutes	Stir every 30 seconds after the first minute until almost dry, then finish at room temperature
University of Wisconsin¹	4 or 5 branches between paper towels	2–3 minutes	Another 30 seconds if not brittle
America’s Test Kitchen⁷	Not stated, on a paper towel	30–40 seconds	Crumble and store

Start with a minute or less, then check every 30 seconds until the leaves crumble. You may read that the microwave keeps mint looking better than other methods do. We found no source for that, and the Wisconsin guide rates microwaved herbs as poor in quality.

Two safety points apply whatever timing you use. If the load is too small, the paper towels can catch fire, Penn State warns.⁴ And Oregon State says not to use paper towels made from recycled paper, which can contain metal scraps that arc.⁵ The Wisconsin guidance calls the microwave a last resort that cooks the herbs and gives very poor quality. It notes that the heat drives off some of the oils along with the water, so microwaved herbs may taste less intense than herbs dried other ways.¹

Where the guides disagree

Question	What named sources say
Dehydrator temperature	95–115°F, up to 125°F where humidity is high (NCHFP, Tennessee, Oregon State)³⁵⁶; 95–110°F (Penn State)⁴
Air-drying time	Generally 2–4 weeks for sturdy herbs hung in bundles (Wisconsin)¹; usually 5–10 days for tender herbs hung in small bunches inside bags (Oregon State)⁵
Microwave time	From 30–40 seconds (America’s Test Kitchen) to 2–3 minutes per cup (Penn State, Tennessee); see the table above
Oven	Lowest setting up to 180°F with the door open for 3–4 hours (Penn State, Wisconsin)⁴¹; or no heat but the oven light or pilot light, overnight (NCHFP, Tennessee)³⁶

We didn’t find a side-by-side test of these on the same herb, so we haven’t picked a winner. Where you get a range, start low and check often.

What drying does to mint

Drying changes mint’s character, and the method matters. A 2003 study dried spearmint three ways: in an oven at 45°C (113°F), in air at room temperature, and by freeze-drying.² The 45°C oven and room-temperature air did best, while freeze-drying lost a lot of certain aroma compounds. To the nose, drying cut the herbaceous and floral notes and made the mint smell mintier.² The study only covered spearmint. We found nothing comparable for peppermint.

America’s Test Kitchen puts mint among the herbs better used fresh, because delicate herbs get much weaker once dried.⁷

How to tell it’s done

The herbs are dry when the leaves are crisp and crumble easily between your fingers and the stems break when you bend them. The leaves should also fall off the stems, Oregon State says. Strip the leaves and toss the stems.

Check again after you pack them. Wisconsin’s advice is to watch the filled containers for a couple of days. If you see any moisture, take the herbs out and dry them longer.¹

Air-dried herbs can carry bugs. The University of Tennessee says air-dried herbs and seeds need treating to kill insects and their eggs, either by heating at 160°F for 30 minutes or by freezing at 0°F or lower for at least 48 hours. It recommends freezing for better flavor.⁶

Storing dried mint

Keep the leaves whole and crumble them as you cook. Penn State says storing herbs whole is preferred. Use airtight containers somewhere cool, dry and dark, away from the stove and sink. Dried herbs can also go into airtight containers in the freezer, Oregon State adds.

How long dried mint keeps depends on who you ask, and none of these numbers was measured on mint:

Source	Scope	Figure
Penn State⁴	Most home-dried herbs	Keep well for up to a year
Oregon State⁵	Home-dried herbs	Up to one year; for best flavor, use within six months to a year
University of Wisconsin¹	Home-dried herbs	Keep for years, but use within a year for best flavor
America’s Test Kitchen⁷	Herbs dried in the microwave by its method	Up to 3 months, airtight
McCormick⁸	Leafy dried herbs, a spice company’s own guidance	1–3 years

They don’t agree, so we’ve left them side by side. McCormick defines shelf life as how long spices stay most aromatic, and that’s the right way to read every number here: a quality window, not a safety date. The real test is your nose. Crush a pinch, and if the smell is faint, the mint has faded.

Herbs in oil are a separate food-safety question. A 2011 review of home-prepared vegetables and herbs stored in oil says to refrigerate them and use them within four days or throw them out, and calls freezing the safest option.⁹

Not yet measured

How home drying methods change peppermint’s aroma compounds.
How long home-dried mint keeps, measured on mint rather than herbs in general.
Microwave times by oven wattage for mint.

Drying Herbs, Wisconsin Master Gardener Program, University of Wisconsin-Madison. mastergardener.extension.wisc.edu · Reference work ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹
Díaz-Maroto et al., Journal of Agricultural and Food Chemistry, 2003 (abstract). pherobase.com · Peer-reviewed ↩ ↩² ↩³
Herbs (drying), National Center for Home Food Preservation. nchfp.uga.edu · Reference work ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹
Let’s Preserve: Drying Herbs, Penn State Extension. extension.psu.edu · Reference work ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹
Drying herbs (SP 50-921), Oregon State University Extension Service. extension.oregonstate.edu · Reference work ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷
Drying Herbs, University of Tennessee Extension. lawrence.tennessee.edu · Reference work ↩ ↩² ↩³ ↩⁴
When You Should Actually Use Dried Herbs, America’s Test Kitchen. americastestkitchen.com · Publication ↩ ↩² ↩³
How Long Do Spices Last?, McCormick. mccormick.com · Merchant ↩
Nummer et al., Food Protection Trends, 2011. foodprotection.org · Peer-reviewed ↩

Also drawn on

Preserving Herbs by Drying (Stacy Reed, updated 3 May 2024), Penn State Extension. extension.psu.edu

How to Dry Mint Without Losing It to Mold