A biodome, or a terrarium, is a miniature self-supporting ecosystem. Biodomes are a wonderful way to teach children about the basic cycles that allow us to live on earth. Biodomes are also a great way for gardeners to grow plants that do not require much maintenance. Biodomes cycle water and nutrients so they do not need to be watered at all. Even if you don't have much of a green fingers, you can still have a successful biodome garden.
Lay down 1 to 2 inches of small pebbles in the bottom of your container. This will allow the plants to drain adequately.
Sprinkle an even, thin layer of activated charcoal on top of the pebbles. This will help to keep the water and air in the biodome clean.
Place a layer of sphagnum moss on top of the activated charcoal. Layer enough potting soil on top of the moss for your plants to be able to take root. Aim for at least two inches of soil.
Pot your plants into the soil. Water them with enough distilled water to dampen the potting soil.
Place the lid tightly on the biodome and keep it in an area where the plants will get adequate sunlight.
Choose plants that have similar requirements for sunlight and water. Activated charcoal is not the same type that is used for grilling. You can purchase activated charcoal at most aquarium stores.