The NASA Clean Air Study: What It Really Found
Editorial note: Earlier outcome statements in this guide require source-specific review and are not presented as current DecorPalm recommendations. Please use the source and scope notes above for general context.
The honest answer is nuanced. The NASA study was conducted in small, sealed chambers — very different from a typical home with its air exchanges, ventilation systems, and much larger volumes. A 2019 meta-analysis published in the Journal of Exposure Science & Environmental Epidemiology found that you would need between 10 and 1,000 plants per square metre to match the air-cleaning effect of simply opening a window.
Peace Lily (Spathiphyllum)
Spider Plant (Chlorophytum comosum)
Snake Plant (Sansevieria trifasciata)
Boston Fern (Nephrolepis exaltata)
Bamboo Palm (Chamaedorea seifrizii)
Rubber Plant (Ficus elastica)
Particularly effective at removing formaldehyde. Its large, glossy leaves are visually striking and make a strong biophilic statement. Prefers bright indirect light.
Aloe Vera
English Ivy (Hedera helix)
Research has shown that English ivy can reduce airborne mould particles by up to 60% in 12 hours — making it particularly valuable for people with allergies or asthma. Effective at removing formaldehyde. Can be grown as a trailing plant or trained up a trellis.
How Many Plants Do You Need?
Use our Air Quality Plant Selector to find the best plants for your specific air quality concerns and room conditions.
Avoid overwatering: Waterlogged soil can harbour mould, which may worsen air quality. Allow soil to dry appropriately between waterings.
Combine with ventilation: Plants work best as a complement to good ventilation, not a replacement for it. Open windows when possible, and use plants to maintain air quality in between.
Frequently Asked Questions
Can plants help with allergies? Some plants, particularly English ivy, have been shown to reduce airborne mould particles. However, some people are allergic to plant pollen or mould in potting soil. If you have allergies, choose low-pollen plants and use well-draining, mould-resistant potting mixes.