Houseplants promise to clean indoor air — but do they work?

Houseplants are a classic decorating tool, but leafy indoor greenery might also be good for you.

The health benefits of plants, some scientists say, can include removing toxins such as benzene — a volatile organic compound in gasoline that’s known to cause cancer — from indoor air.

And with air quality — especially in the post-pandemic era — on a lot of people’s minds, houseplants are sprouting up everywhere.

Now, a new study claims that Ambius, a manufacturer of sleek “green walls” that display indoor plants, has come up with a design so effective at removing indoor air pollutants that 97% of toxic compounds, including benzene, were removed in just eight hours.

“This is the first time plants have been tested for their ability to remove gasoline-related compounds, and the results are astounding,” University of Technology Sydney professor Fraser Torpy said in a news release.

But other scientists are throwing cold water on plants’ supposed ability to clean indoor air.

In 2019, researchers examined how quickly and effectively plants could remove VOCs.

Their study showed that it would take roughly 10 to 1,000 plants per square meter to improve air quality as much as a typical building ventilation system can.

In a 1,500-square-foot house, that amounts to a dense jungle of at least 680 houseplants.

“Plants, though they do remove VOCs, remove them at such a slow rate that they can’t compete with the air exchange mechanisms already happening in buildings,” Michael Waring, study co-author and environmental engineer at Drexel University in Philadelphia, told National Geographic.

Another business, Paris-based start-up Neoplants, now sells a “superplant” that reportedly has been genetically engineered to clean the air as well as 30 ordinary houseplants.

Though it looks like a regular pothos houseplant — a familiar ivy with heart-shaped leaves — the Neo P1 sells for $179.

The plant also requires “power drops,” bacteria supplements that must be purchased and added each month to the plant’s soil to help it continue breaking down VOCs.

“As soon as you ship a product to somebody, the viability of these bacteria declines,” Jenn Brophy, a Stanford researcher whose lab develops genetically engineered plants, told MIT Technology Review.

“It would be so wonderful if we had all these beautiful plants that clean our air for us,” Elliott Gall, a professor at Portland State University who studies indoor air quality, told National Geographic. “But there are more effective ways of cleaning indoor air.”