True closed Terrariums are always sealed with a lid, meaning they are much lower maintenance and mostly self sufficient.
These kinds of ecosystems require a healthy balance, so can be a bit harder to set up than an open Terrarium. Its important to not over water a closed Terrarium, they should only need a small misting of water every few months. If there’s condensation forming on the glass, then your plants are being watered and you don’t need to add more.
Plant selection for a closed Terrarium is very important as plants in this environment need to be able to handle the warmer temperatures and high humidity of this environment. Think ferns, mosses, begonias, fittonias for example, as opposed to succulents and cacti which will rot in this moist environment.
Most plants selected for closed Terrariums are found in the wild growing under a big jungle canopy, with only filtered and dappled sunlight, so they need these conditions in a Terrarium too.
Never place your Terrarium in direct sunlight as this will turn your ecosystem into a hot mess and your plants will quickly burn and die. The best rule of thumb is to place your Terrarium in a north facing window (think cooler morning light), somewhere it can see the sky outside but not in direct line with the sun streaming in the window. Once your Terrarium has found its happy place it can survive for many years with very little maintenance.
