Attached plants
Terrarium plants - Perennials - Green up your terrarium!
Especially in the tropics and subtropics, many plants grow as epiphytes. Epiphytes grow on trees and shrubs, while plants on rocks are called lithophytes or epiliths. Some of the same species occur as both epiphytes and lithophytes, while others are more specialised. Epiphytes often have special adaptations to hold on and obtain sufficient water and nutrients, such as adhesive roots, water-storing "cisterns" or humus-collecting leaves. Some are in symbiosis with ants. Many epiphytes need a certain layer of loose substrate in which to root and can also be kept as ground or pot plants. However, there are also very "air plants" that only form adhesive roots or are completely rootless. Tillandsias, for example, absorb water and nutrients from precipitation and moist air via suction scales on their leaves, while orchids do this via a special layer of cells on their aerial roots.