The word "terrarium" means "little world." These containers create an environment for plants that would not necessarily survive in the home environment. They are lidded or open clear glass containers in which plants grow. Terrariums, once established, require significantly less care than pots or outdoor plantings. For shade plants, and especially for tropical plants that like shade, terrariums can create the perfect environment.
Place a single layer of gravel on the bottom of the terrarium. Make sure to cover every open space. This is the drainage layer that is essential for preventing root rot.
Lay down a half inch of activated charcoal. This will help with drainage and neutralize any chemicals that may build up in the terrarium, especially in a closed terrarium. Place a layer of sphagnum peat over the charcoal to prevent the potting medium from dropping into the drainage layers.
Pour a mix of peat and perlite into the terrarium, enough to take up one-fourth of the container. Moisten the medium, but do not soak it because it is difficult to remove water from a shade terrarium.
Plant shade-loving plants in the terrarium. Mosses, ferns and some tropical plants including rue anemone, black mondo grass, ground ivy and wild ginger will work in a shade terrarium. Arrange the plants in an attractive manner.
Moisten the terrarium soil medium once every four to six months in a closed terrarium. In open terrariums, you will need to water more often to keep the soil moist, but still less than a regular pot. Most terrariums fail because of overwatering, so water sparingly.