It shows off the form and texture of succulents, just as any container garden. Christmas cactus is an excellent example. This allows for good airflow, and less humidity in the outdoor terrarium. This plant can reach 1.5 feet in height. It doesn't need much water and it thrives in indoor conditions. "This group is going through mitosis." The plump cells were firm when I touched them with my fingertip. Nancy began her succulent mermaid’s garden several years back.