Question for Pat from Stephanie: I'm setting up a new office and want to create a bit of an indoor ecosystem with a collection of potted plants. Any recommendations on the best plants what will be happy indoors (in Johannesburg) and give off the best oxygen ratio? I guess the larger question is what is the difference in types of plants and carbon dioxide to oxygen exchange. Is an aloe equivalent to a ficus, for example?
Pat’s Answer: Plants performing photosynthesis absorb carbon dioxide and release oxygen, so indoor plants can increase the amount of oxygen and reduce the amount of carbon dioxide inside a building. The resulting impact on indoor air quality depends on the level of air exchange with the outside - a tightly sealed building would benefit more from the plants than a drafty building.
The rate of plant growth is the main factor determining which plants are better at increasing oxygen levels. Fast-growing plants absorb the most carbon dioxide and release the most oxygen. Also, some plants, including orchids and succulents, continue to release oxygen at night, not just during daylight.
The U.S. Lung Institute lists the following as the Top 5 houseplants for increasing oxygen indoors:
Indoor plants also raise humidity levels inside buildings, which helps reduce respiratory and skin problems caused by dry air often found in offices. People with plants in their offices are more energized and able to focus and feel less stressed.
Indoor plants, when in a well-sealed building, also help clean the air by soaking up volatile organic compounds (VOCs). Based primarily on NASA research, the following table lists the top 10 house plants for air purifying.
For more information, see:
Claudio L. Planting Healthier Indoor Air. Environ Health Perspect. 2011 Oct; 119(10): a426–a427. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3230460/
Conklin LM. The 18 best air-cleaning plants, according to NASA. https://www.msn.com/en-sg/lifestyle/smart-living/the-18-best-air-cleaning-plants-according-to-nasa/ar-BBVyqYM
Li Q. Forest Bathing: How Trees Can Help You Find Health and Happiness. New York, NY: Viking (2018).
US Lung Institute. Top 5 Plants for Increasing Oxygen. https://lunginstitute.com/blog/top-5-plants-for-increasing-oxygen/
Wolverton BC. How to Grow Fresh Air: 50 House Plants that Purify Your Home or Office. New York, NY:Penguin Books (1997).
Anna Lentz, artist, writer, and creativity coach who blogs about making a creative life connected with nature at Spring Bird.