It's simple to create a mini terrarium for your air plants. Live air plants do not need soil - weird and cool, I know! So, instead of dirt, you can use things like seashells, sand, rocks. I have been hanging on to a mason jar of tiny seashells my kids collected a year ago. I knew if I waited long enough, the right seashell craft would come along. And it finally did. Not long ago, I saw an air plant terrarium on the Pottery Barn ...