A plant terrarium is a glass enclosure that contains a closed ecosystem consisting of plants. Because most terrariums are enclosed, there is very little water loss and the water circulates within the container.
All the plants that you put in your terrarium must have the same or very similar requirements, because they're sharing the same space. They should have similar:
In selecting plants for your terrarium, you also need to consider the size of your container. A small terrarium forces you to choose smaller plants. A bigger one gives you more choice.
Although the plants should have similar growing requirements, you also want to select a variety of plants to make it interesting.
Plant the bigger plants in towards the back to prevent them from hiding or obscuring the smaller plants.
It's nice to give your terrarium extra character by deciding on a theme. The theme can be created either by using similar plants or by using similar decorations.
Put decorations in your plant terrarium to liven things up a bit. Pieces of wood are always a popular choice, but you can put any objects in to suit your theme. Moss is fantastic to use as a ground-cover to cover open bits of soil. Fake lichens or mushrooms can be used to add some extra realism to your display.
As with plants, bear in mind the size of your plant terrarium when choosing decorations. You don't want an object to look overcrowded or out of place. Or too small and lost for that matter.
How about trying a desert theme with cacti and succulents and lovely red desert sand? You'll need to keep the terrarium open or very well ventilated to prevent the plants getting too much moisture. Or maybe a tropical theme with moss as a ground-cover.
A medieval theme can contain little people, castles and quaint houses in a lush forest environment. You could have a bonsai theme where a bonsai tree forms the centre of your display. The options are really limitless!