For years, I've heard that certain houseplants help keep indoor air clean by removing pollutants. Bill Wolverton, former NASA scientist, confirms this fact in his book How to Grow Fresh Air: 50 Houseplants that Pruify Your Home or Office. In his book, Wolverton rates plants on four criteria: effectiveness in removing the three main indoor pollutants (formaldehyde, benzene, and carbon monoxide); ease of growing; resistance to insect and disease; and ability to transpire (release) moisture. Based on those criteria, the top three houseplants were Lady Palm (Rhapis excelsa), Rubber plant (Ficus robusta), and English ivy (Hedera helix).
Wolverton estimates that you need two or three full-sized plants (in 10- to 12-inch containers) per 100- to 150-square-foot room for best results. If you don't have enough room for full-sized plants, place plants in ″breathing zones″ in your room, such as near the bed or office desk, for optimal results. These easy to care for plants will help create an indoor garden that will promote clean air conditions.