A hanging Ant Plant and Spanish Moss. The Spanish Moss, is not a moss buy an epiphite, found hanging from trees and absorbing moisture from the air. The Ant Plant has a symbiotic relationship with ants, allowing them to live inside naturally-occuring openings, and using the ant waste as a fertilizer.
The moss will grow on its own with enough water alongside the Ant Plant, as moss can grow anywhere. Add fertilizer to the Ant Plant if no ants are available to provide it nutrients.