Which plants to choose?
There is an ongoing discussion about the types and numbers of plants needed in homes to achieve health benefits. However, the greater the number of plants used, the more likely the benefit to air quality and overall well-being.
Below is a list of easy to grow foliage houseplants, which could be grown in homes, schools and offices. They have attractive leaves and an ability to withstand the environmental conditions typically encountered indoors (tolerance of shade and fluctuating temperatures). In addition, they are usually inexpensive and easy to maintain.
Indoor foliage plants and the VOCs they have the potential to reduce
(data summarised from the review article by Dela Cruz et al., 2014)
Benzene and formaldehyde (to varying degrees)
Chlorophytum comosum (spider plant)
Dracaena fragrans ‘Janet Craig’ (dragon plant)
Dracaena marginata (v) AGM (Madagascar dragon tree)
Epipremnum aureum AGM
Ficus elastica (India rubber tree, rubber plant)
Hedera helix (English ivy, common ivy)
Nephrolepis exaltata ‘Bostoniensis’ (Boston fern)
Sansevieria trifasciata (mother-in-law’s tongue)
Syngonium podophyllum AGM (Nephthytis)
Zamioculcas zamiifolia (fern arum)
Formaldehyde (to varying degrees)
Aglaonema ‘Silver Queen’ AGM (Chinese evergreen ‘Silver Queen’)
Rhapis excelsa AGM (bamboo palm, lady palm)
Spathiphyllum sp. (peace lily)
Benzene (to varying degrees)
Aspidistra elatior AGM (common aspidistra, cast iron plant)
Chamaedorea seifrizii (bamboo palm)
Crassula ovata (syn. Crassula portulacea) AGM (jade plant, jade tree)
Dieffenbachia ‘Tropic Snow’ (v) AGM (dumb cane)
Howea forsteriana AGM (flat palm, Kentia palm)
Limitations of our knowledge
It is worth noting that there are issues with interpreting this wide range of scientific studies for real-life-situations. The fact that they are conducted under different experimental conditions, and that the results of VOCs removal are expressed in differing terms, make direct comparisons a challenge.
The reported rates of removal even within species/cultivar vary greatly, and will depend on the starting concentrations of measured chemicals, environmental conditions within the experimental space etc. Further research is essential in order to replicate typical home and office environments to assess plants’ true impact on the quality of air indoors. Growing media, temperature and light intensity all have an effect on the rate and efficiency of VOCs removal. In a real-life setting, air exchange will vary compared to research undertaken in sealed chambers.
In addition, human well-being is a complex issue. Scientific research is beginning to evaluate the effect plants have on different aspects of this subject. Types of plants, their arrangement and factors such as scent and colour are also being investigated.