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Are houseplants an economical way to purify indoor spaces?

Aloe Vera

Some people believe that indoor plants could provide an affordable solution to air quality problems. Although there are devices that can purify the air, they are not within everybody’s budget, however, plants can be grown by anyone at a low cost. But are they really beneficial?

Studies suggest that the impact on air quality is minimal, but a wall covered with plants could make a difference – according to some research that shows plants as a possible source of indoor wellness.

In other words, indoor plants could contribute to the purification of closed space air, however, their results are not potent. In places where air pollution is lower, it is often more beneficial to open the windows.

However, plants serve different functions. Certainly having plants at home can help make living spaces more pleasant, healthy and add a natural decorative touch that always looks great indoors.

Why is it commonly assumed that houseplants can purify the air?

In 1989, NASA scientist Bill Wolverton investigated whether plants could remove some pollutants, such as VOCs, that are frequently released by household products. Based on the results of the study, Wolverton claimed that plants could be an inexpensive solution to remove indoor air pollution from homes.

The scientist found that indoor plants can remove VOCs in an airtight laboratory environment. Subsequent studies have confirmed that certain plants, to a greater or lesser extent, are air purifiers. In addition, the microorganisms in the soil of the plants would also help clean indoor air.

So, with this information, plants placed inside the house gained popularity, many people have visited gardening stores asking for the best ones to purify the air. However, subsequent studies have indicated that the effect is not very significant.

What does recent research say?

While some defend Wolverton’s position, other researchers argue that the evidence is inconclusive or, at best, the removal of particulate pollutants is modest.

A study published in the journal Building and Environment (2017) indicated that indoor plants had little effect on the home environment. The tests were conducted by simulating the effects in a typical U.S. home.

“Indoor vegetation is often proposed as a passive approach for improving indoor air quality. While studies of outdoor environments indicate that vegetation can be an important sink of outdoor ozone, there is scant data in the literature concerning the dynamics of ozone uptake by indoor plants,” according to the publication.

Some experts do not doubt indoor plants can eliminate toxins; however, they believe that the results are no greater in an uncontrolled environment outside the laboratory. In other words, many studies have been conducted in small, sealed environments, while conditions in a house are quite different.

A study recently published in Air Quality, Atmosphere & Health (2022) indicated that some plants can remove nitrogen dioxide (NO2). Meanwhile, other research published in the Journal of Environmental Management (2020) argues that a single plant won’t make a difference, but a green wall could help.

“Internal green wall systems can be combined with building structures to bring positive impacts on people’s quality of life in interior spaces.”

While you might think, in large quantities, plants could improve air quality, there are other factors to consider such as: Not everyone is a dedicated plant lover and capable of caring for a lot of them. In addition, a big stock of interior plants can lead to other problems such as humidity and mold.

Other benefits of indoor plants

Despite the different stances of science, you should not be dismayed. You can still choose beautiful houseplants to help improve your health, as it has been shown indoor plants can help calm the nervous system and improve your mood, making you happier and more relaxed, increasing your energy levels and making excellent life companions.

While scientific research continues, you don’t have to sacrifice your love of plants. If you want to give the air purification hypothesis a chance, here are some commonly recommended plants to keep at home:

  • Aloe vera
  • Rubber tree
  • Areca palm
  • Clivia
  • Chinese evergreen
  • Chrysanthemum
  • Philodendron
  • Croton
  • English ivy
  • Peace lily
  • Zanzibar gem
  • Mother in law’s tongue
  • Dragon tree
  • Barberton daisy
  • Spider plant
  • Weeping fig
  • Broad lady palm
  • Scarlet star bromelia

Image: paweesit