Plants as Air Purifiers?

IF you lived in a sealed environment like a spaceship or biodome, then plants could be extremely helpful in reducing harmful VOCs (check out NASA’s BioHome).  Since most of us live in a much more dynamic environment with many air leaks, entrances and exits, a new study calculates you would need a virtual forest (like between 1,000 and 10,000 plants per 10 ft2 of floor space) to reap the benefits of higher indoor air quality due to plants alone.  That said, we still want to advocate for plants. Why?

  • According to the creator of NASA's BioHome, Bill Wolverton, the VOC absorption rate of a plant has direct ties to ventilation of the roots.  He worked with a Japanese company to create the EcoPlanter, a Plant Air Purifier, which supposedly allows one plant to do the work of 60 or more plants in terms of eliminating VOCs.  This concept is being updated radically to add newer technology such as a PCO filter and UV light, in startup company Koru, that combines the power of AI with the plant's natural air filtering qualities.  It will self-care for the plant, monitor air quality, never need filter changes and eliminate 99% of air pollutants. Plus, it looks better than an air purifier!  
  • Some plants are great at removing nitrogen dioxide (NO2), which is a common air pollutant from vehicle emissions. In a study conducted by the University of Birmingham in the UK, a Peace lily (Spathiphyllum wallisii), Corn plant (Dracaena fragrans) and fern arum (Zamioculcas zamiifolia) were all tested in separate chambers, and each was able to remove about half of the NO2 in their chamber, within an hour.  The size of the chamber relative to the size of a normal office or apartment, would require about 5 plants to reduce NO2 pollution by about 20%. Way to go, plants!
  • If you have limited floorspace for pots but still want the maximum number of plants, there are a number of companies who can help you install plant wall systems for a dramatic and multiplied air purifying effect.  
    • has easy installation videos for their free-standing or wall systems, and you can purchase their plants or your own (tips are provided for preparing your own plants).
    • has pre-built walls and dividers for purchase
    • and create custom walls for your home
  • For many years I was fascinated by a friend’s pet fish and plant combo: The peace lily fed off the nutrients (waste) of the betta fish and the plant returned clean water to the fish: a win-win situation especially when you consider the much-reduced need to clean the fish tank!  However, there are disadvantages to the fish in a simple flowervase/tank: its diet, breathing, and temperature are not regulated well.  The ideal environment for these type fish incorporate an air bubbler, filter and heater, in all called an “aquaponics fish tank”.  AquaSprouts is a company that has a few setups that keep the fish in a much better environment than a vase.   It’s a science that kids will want to learn and participate in, too.   
  • Then, there is the psychological effect of plants : they do good things for the ambiance of our environment and our overall well-being!  This one page cites dozens, if not hundreds of benefits of plants and interaction with plants, shown by studies.  Indoor plants and spending time amongst outdoor plants boosts memory retention, increases attention span, and has a calming effect on our brains, enabling us to focus on the task at hand.  Flowers and ornamental plants reduce stress levels, contributing to moods of  relaxation, security and happiness.  In the hospital, plants in patient recovery rooms accelerate healing, even more so with patients who participate in plant care.  Plants increase our empathy and compassion for others, improving relationships.  Increased energy and learning ability are also results of environments beautified by plants.  With all these benefits, who can say no to adding a few plants in their home or office?
  • If your home is naturally on the more humid side (over 50%), then there are plants that can absorb water from the air through pores in their leaves (stomas), helping you to dehumidify.  Xerophytes and Epiphytes are examples of this (plants you would see growing in warm climates).  Air plants (tillandsia), boston ferns and peace lilies also make fine dehumidifying partners (see photos and more plants here)! 
  • If you live in a dry climate, plants that require more water will naturally “humidify” a room.  Evapotranspiration is the method in which plants move water from their roots through the stems and leaves, into the air through their stomas.  This study indicates that “ 25 spider plants in 4-inch-diameter pots or fewer, larger plants, could increase the humidity of an interior bedroom from 20% RH to a more comfortable 30% RH under bright interior light conditions.”  If you don’t have a lot of bright light in your living area, you can switch to jade plants, which do more of their evapotranspiration during dark periods.  Here is a list of other plants with humidifying benefits.  Who knew?
  • Plants are easy additions to decor: from classic ferns to eclectic cacti and orchids, you can use a plant to add style to any room.  There are also species of plant available for every skill level, from beginners to the serious green thumbs, and thankfully some of the best at eliminating indoor toxins are among the hardiest!     Here are some super-easy, common varieties to invite in (trust me these are really plants, not insects):
    • Spider plants 
    • Snake plants
    • Aloe Vera
    • Boston Fern