Breathe Easy
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Breathe Easy

Don’t snub houseplants as merely decorative. Some of these can filter out pollutants, harmful gases, and airborne waste.

Let’s face it: air pollution is everywhere. On bad days, the moment one leaves the house, one can smell smoke, haze, or the stench of rotting food from the bins behind restaurants.

But your home isn’t safe, either. Many household items - carpets, clothes, pillows - contain factory-based chemicals used in their manufacture that can emanate when you use these objects. For example, styrene is a volatile organic compound (VOC) used in latex backings for broadloom carpets and is a known carcinogen and trigger for asthma. Memory foam pillows generally contain more chemicals, including VOCs, than any other type of pillows. Most clothes labelled ‘no iron’ contain perfluorinated chemicals (PFCs) to maintain the wrinkle-free effect. PFCs can cause skin rash and breathing difficulty.

So, what’s the best solution to this problem? Houseplants! Not just any houseplant, but ones that clean up the air and add a touch of warmth and lived-in feel to your precious space.

Growing plants indoors can be difficult unless you live in a house with high ceilings and big windows that allow plenty of light in. Growing plants next to big windows or even next to balcony sliding doors would work best. Succulents and cacti prefer direct sunlight, although there are some succulents that can tolerate low light, such as sansevieria and Zamioculcas zamifolia (aka ZZ plant).

“Most imported plants come in planting media that are too wet for tropical Singapore,” advises Sandy Soh, a landscape consultant and plant enabler. “It would be better to change out the media to something more well-draining and quick-drying.” He suggests a mixture of soil or burnt earth with volcanic sand or pumice and perlite - “that helps the media be less soggy and compacted”.

Sansevieria (Snake plant)

The snake plant is popular with people who adore houseplants. They come in various shapes, leaf patterns and colours. The common sansevieria, also known as mother-in-law’s tongue, has a yellow strip running the length of the leaf perimeter. It hails from West Africa and is hardy and easy to grow. More importantly, it is ideal for indoor spaces - NASA has proven that this species removes air-borne toxins such as xylene, formaldehyde, toluene and even nitrogen oxides. These are harmful chemicals that can be found in paints, printing materials, carpeting, and plywood, to name but a few. The sansevieria cylindrica resembles spears but their mottled leaf patterns and striking shape add a decorative touch to your home while purifying the air.


This is a must-have plant for gardening newbies. Spanning specimens of different shapes, colour and sizes, a well-maintained species can stand tall and proud in a living room. It’s best to give it at least six to eight hours of sunlight. Some specimens can grow well in direct sunlight. It requires the occasional fertilising (once a fortnight or a month). Note that dracaenas are toxic to cats and dogs. Give this plant ample TLC and it will obliterate toxins such as formaldehyde, xylene, toluene (present in paint thinners), benzene (present in varnishes and lacquers), and trichloroethylene (solvents and degreasers).

Rubber plant (Ficus elastica)

Originating from India, the rubber plant can sprout large roots and creep up buildings. Its deep green to brownish/reddish leaves inject colour to interiors and well-grown specimens are known to have entwined roots that form interesting shapes along the plant’s trunk. The rubber plant can tolerate a range of lighting conditions, from dappled to direct sunlight. While its sap is harmful to domestic pets, its ability to filter out carbon monoxide (present in vehicle exhaust fumes), formaldehyde and trichloroethylene far outweighs the cons.


This is a perennial favourite among gardeners because of its wide range of colours, sizes, and leaf shapes and patterns.


  • Trim dead leaves when you spot them
  • Repot your plant once every year
  • Try to stick to slow-release fertilisers
  • The plants listed in the article love organic fertiliser (rice water, seaweed, fish oil, goat poo pellets)
  • Ensure that these plants get their ample dose of sunlight
  • Get grow lights if your home does not offer natural sunlight

Found mostly in the tropical forests of Asia, it has been hybridised in many nurseries around the world to make it more resilient to other weather systems. It is also easy to grow and flower, requiring minimal fertilising (once a month with rice water or store-bought fertiliser pellets). Best of all, it tolerates a wide range of lighting environments; in fact, some darker-leaf varieties grow well in the shade! The plant’s sap is particularly harmful to dogs. The aglaonema is excellent for obliterating noxious, imperceptible gases, so they are great for families with young children.

Aloe vera

This succulent comes in many varieties. Not only has aloe vera been used by Egyptians for more than 6,000 years, the plant’s core - its gel - is used to heal wounds, cool sunburns, soothe cuts, and calm itches. Ensure that the plant gets maximum sunlight since it belongs to the cactus family. It is extremely easy to care for and doesn’t require special treatment. Best of all, this hardy plant doesn’t even require regular fertilising and can go without water for weeks. The plant is renowned for absorbing formaldehyde and benzene.


Sandy Soh, a landscape consultant and plant enabler (www.facebook.com/terrascapesllp) shares his views on having plants at home:

Is there a limit to how many pots of plants a room should accommodate?

More plants would be aesthetically more pleasing, but only if there’s enough space and light for the plants to grow.

What is a misconception about houseplants?

That plants cannot do the work of a true-blue electric air filter in terms of output and efficiency.

Why are people more concerned about the health of their environment?

There is more awareness of global warming, clean living, recycling, etc. I’ve noticed a steady increase in the number of people who are into growing plants - not just as a hobby but also to beautify their homes.

What should people consider first before considering having houseplants?

Light levels are the most important. It is imperative to select the right plants for their growing environments. No point getting a sun-loving plant when you can’t give it sufficient direct sun.