Rinse the lemon balm under cold water and spin it in a salad spinner or shake it well to get excess water off.
Make small bundles of 3-6 stems, keeping a nice section of stem at the top without any leaves (this is where the string will go)..
Tie the bundles together with a piece of string. You’ll want to tie them very tight, as the stems shrink when they dry out.
Hang the lemon balm bundles in a dry place with good air circulation. How long it takes to dry the herb will depend on how dry your air is and how much airflow they get. I usually leave mine for a couple of weeks.
Once the lemon balm is completely dry, grab the bundle with the palm of your hand and squeeze to break the leaves off of the stems.
Crunch the dried leaves up until they are your ideal size, then store in an airtight container out of direct sunlight.
Dehydrator
Rinse the lemon balm under cool water and spin it in a salad spinner. Allow it to air dry for a couple of hours to ensure all excess water is dried up.
Spread the lemon balm leaves out in a single layer on dehydrator trays.
Set the dehydrator to a low setting (around 100°F) and run it until the lemon balm is completely dry and crispy, around 12 hours. Check regularly around the 12-hour mark.
Turn off the dehydrator and allow the leaves to cool to room temperature. Crunch the leaves up and store the lemon balm in a glass container.
Notes
I don’t recommend drying lemon balm in the oven. I tried it, and the tender leaves just burn too quickly.
Lemon balm is best harvested in late spring or early summer, before it has flowered. Only harvest up to ⅓ of the lemon balm plant at a time.
Learn how to properly harvest lemon balm in my tutorial about how to harvest mint.
Don’t leave your dry lemon balm hanging for too long. It can start gathering dust.
If you live in an extremely humid area, you might find that your lemon balm molds before it’s able to dry out. If that’s the case, I would recommend investing in a dehydrator.
Dried lemon balm is at its best for up to a year. It’s still edible after that, but the color and flavor will start to fade.
Dried herbs should be stored in a dark place to preserve their color and flavor for as long as possible.