#4: English ivy.
Grown outdoors, English ivy is an invasive species that can damage your home's exterior and tear off your gutters. But bring it inside, and it's an effective formaldehyde remover. Thanks to its ability to climb structures, it's easy to grow as topiary and use as a decorative element in your living spaces. English ivy likes part sun and part shade, so it's a good plant to try indoors, and it's not as temperamental as Boston ferns are. Occasional waterings and mistings during the winter will keep it healthy.