How to Preserve Peppermint and Spearmint by Drying or Dehydrating

Air Drying
Peppermint and spearmint is best air dried by hanging it upside down from the stem with the leaves in tact. The stems should be cut 5 inches above the surface of the ground to keep the plant healthy for the next growing season. Air drying can sometimes cause the leaves to brown.

Drying in a Dehydrator
Remove the leaves from the stem and place them on a drying tray. You may want to line the tray with plastic wrap prior to drying. This is the most effective way to dry peppermint and spearmint as the leaves retain their color best in this method.

Drying in the Oven
If you do not have a dehydrator, you can dry peppermint or spearmint in the oven by setting it to a very low temperature. The temperature should ideally be between 90 and 110 degrees. Lay the leaves out on a flat surface and place them in the oven checking them often.