Plants Provide Natural Indoor Air Filtration

If recent fires in California are any indication of the future (and it is predicted that they will continue) we all need better air filtration in our homes. In addition to electronic air filters and wearing masks indoors, houseplants are a good idea, doing double duty by adding beauty to your home.

With the Camp Fire still on our minds and victims still in our hearts, one positive thing we can do is be prepared for what may come next summer and fall. Over the course of a couple weeks, the smoke that took Bay Area air quality to unhealthy levels and closed schools and businesses also filtered into our homes, sending thousands fleeing to Tahoe or the Central Coast.

Air filtration units became scarce at local home improvement stores, and many of us who stayed in town flocked to plant nurseries to filter inside air naturally. I looked at four stores that sell houseplants, including Ace Hardware, which has less stock in the cold season, Sloat Garden Center in Pleasant Hill, Lowes and Home Depot. I was in search of specific plants on a list generated from a famous 1989 NASA study, “Interior Landscape Plants for Indoor Air Pollution Abatement.” What I found was that there was a run on spider plants, Dracaenas, snake plants and others that are particularly affective in filtering air. Happily, I was able to cobble together several large plants on the list, from Sloat and Lowes.

Toxic smoke from fires is not the only thing adding to decreased air quality around the Bay. With the recent population surge, auto and truck traffic has significantly increased, affecting air quality. In 1980, when I first moved to the Bay Area, the population of San Francisco (city and county) was 678,974. In 2017 it had grown to 884,363, according to uspopulationreview.com. Population has also grown around the Bay, especially the South Bay.

In Solano County, the population has almost doubled since 1980, from 235,203 to 445,458 in 2017. According to the Metropolitan Transportation Commission, those numbers will continue to swell in the Bay Area. From 2020 to 2040, the Bay Area is projected to grow from 7,786,800 to 8,889,000—more than 1.1 million new residents, according to the Association of Bay Area Governments (ABAG).

What can we do to plan for decreasing air quality? Here’s what the NASA study concluded: “Low-light-requiring houseplants … have demonstrated the potential for improving indoor air quality by removing trace organic pollutants from the air in energy-efficient buildings.”

Dracaena Plant in Entryway

We don’t have to grow urban forests in our homes to achieve results; we can strategically use plants to help filter inside air. The NASA study recommends “15 to 18 plants in 6 to 8-inch diameter containers, to clean the air in an average 1,800 square foot house, or roughly one plant per 100 square feet of floor space,” however, the bigger the plant, the better the filtering. Although a few websites take exception to the NASA findings in terms of how much air is being filtered, suggesting the NASA study was done in a controlled environment for astronauts, the NASA study findings are generally accepted.

When our windows are closed due to unhealthy outdoor air, houseplants not only have the ability to help filter toxins, they have been shown to have a positive affect on mood and reduce stress. It’s a win-win.

SIDEBAR

NASA plant list, most of which can be found at local home improvement stores and plant nurseries.

Dwarf Date Palm, Phoenix robelenii

Boston Fern, Nephrolepis exaltata

Kimberly Queen Fern, Nephrolepis obliterata

Spider Plant, Chlorophytum comosum

Chinese Evergreen, Aglaonema modestum

Bamboo Palm, Chamaedorea seifrizii

Devil’s Ivy, Ficus benmamina

Flamingo Lilly, Epipremnum aureum

Weeping Fig, Anturium andraeanum

Lilyturf, Liriope spicata