Epiphytes (or air plants) are plants which grow on other plants, such as a tree, or sometimes upon some other object such as a building. Common epiphytes include mosses, ferns, cacti, orchids and bromeliads and we have gardening information on all kinds of epiphytes. Epiphytes derive their moisture and nutrients from the air and rain and sometimes from debris which accumulates around it. Some epiphytes are large trees that begin their lives high in the forest canopy. Most epiphytic seed plants and ferns are found in tropical and subtropical rainforests because they require conditions of high humidity.