In a dehydrator or an oven (set to 60 degrees Celsius,) dry the lemon balm, lemon zest and ginger until they are completely dry. All the ingredients will take between 2-3 hours to dry depending on the size of the pieces.
When the lemon balm is dry, crumble it your fingers, into small pieces. Break the pieces of lemon zest into small pieces and crumble the ginger slices.
Combine everything in a jar and seal.As long as everything was sufficiently dried, this will last months in a cool dark place.