Four ways to dry mint at home including air-drying, a food dehydrator, a microwave, and the oven. Dry either homegrown mint or purchased and you can have a ready supply to use all year long.
Dry mint in bunches: Tie small bunches of mint by the stem with string and hang them upside down in a warmish, dry, dim, and airy place. To keep dried leaves from dropping down to the floor below, loosely tie a paper bag over the bunch. Leave the mint to hang, and it should be dry in about a week's time.
Drying rack: Another way to air dry mint is to use a drying rack. I lightly spread the mint on, stems and all, and leave it there to dry. If the room is warm enough, it usually takes a week to dry.
Method 2: Dry Mint in a Food Dehydrator
Spread the mint, either plucked from the stems or still on, in a thin layer on the racks of a food dehydrator. Plucked and it will dry faster, though. Dry at 105°F (40°C) for three to five hours or until the leaves are brittle and crumble when rolled between your fingers. Allow to fully cool down before you store the leaves.
Method 3: Dry Mint in a Microwave.
Small amounts of mint leaves can dry quickly in the microwave. Spread clean but dry leaves over a plate so no leaf is touching. Microwave in short ten-second intervals at a low setting until the leaves curl up and are crispy-dry.
It helps to turn the leaves over after about thirty seconds and to open the microwave at the end of each ten seconds. This allows steam to escape. If there's moisture on the plate after the leaves have dried, transfer them to another dry plate to finish drying off on the counter.
Method 4: Oven-dry Mint
Spread plucked mint leaves in a thin layer on a lined baking sheet. Dry the mint in the oven at the lowest temperature until bone dry. Keep the oven door wedged open with a potholder so that moisture can escape. Oven-drying mint this way takes only about ten to fifteen minutes.