Natural light and balanced humidity are the keys to growing tropical plants in the bathroom. Bathrooms often provide two conditions that many tropical plants love: relatively stable temperatures and elevated humidity that increases every time someone takes a shower. Phalaenopsis orchidPhalaenopsis orchids are among the species that adapt best to a bright bathroom. Phalaenopsis orchids add elegance and color while thriving in the humid conditions of a bright bathroom. Madagascar jasmine (Stephanotis floribunda)Not all jasmine species are suitable for growing indoors, but Madagascar jasmine can thrive in a spacious, bright bathroom.