Mailing a kombucha mushroom is actually quite simple! To mail a kombucha mother, put the SCOBY in a Ziploc bag, such as the ones you would use for freezing food. Put some kombucha in there as well for the SCOBY to sit in (which can later be used as starter tea), and seal the bag. Put this bag into another Ziploc bag and seal that too, so the SCOBY is double-sealed. Put this package into a box with some good cushioning so the kombucha mushroom isn't jostled around too much (but also leave a little room for the plastic bags to expand because the SCOBY will ferment and produce CO2 during transportation), and you're all set to mail away! (P.S. I've never actually mailed a SCOBY, but numerous readers have confirmed that this works, and Gunther Frank has mailed kombucha mushrooms all over the world this way with much success!)
This can be handy if you would like to mail a kombucha mushroom to a friend, or to mail a kombucha mother to yourself if you are moving and cannot bring your SCOBY on the plane with you.
However, because plastic is not good for the mushroom in the long-term, it is recommended to transfer the kombucha and SCOBY into a clean glass jar once it arrives! Then you can either begin brewing or put the kombucha mother into storage until you're ready to brew.