A terrarium is an example of an ecosystem which is closed or self-container. Add 4 inches of potting soil.
Planting is next.
Using a spoon or pointed stick, open a place for each plant, set it in and press the soil back around the roots. Lightly water each plant. Close the container. If too much water accumulates in the container, it can be opened for short periods of time. Place the terrarium anywhere in indirect sunlight.