It shows off the form and texture of succulents, just as any container garden. Christmas cactus is an excellent example. This creates a terrarium with more airflow and less humidity. This plant can reach 1.5 feet in height. It doesn't need much water and it thrives in indoor conditions. "This group is undergoing mitosis." When I pressed one with my fingertip, I expected the plump cell to yield like a water balloon, but it was firm. Nancy started her succulent mermaid garden many years ago. She chose plants with unusual shapes and textures that looked like sea creatures or underwater plants.