Houseplants add a splash of lively colour to a room, and many studies have confirmed, they can also improve the air we breathe.

While exploring how to keep good air quality in the confines of a space ship, research by NASA showed that pot plants could play a part.

NASA found that plants’ leaves and roots, together with micro-organisms in compost, remove many toxic chemicals from the atmosphere.

One of the worst toxins is formaldehyde, and it is nearly everywhere in the house. It’s in wood floorboard resins, contiboard furniture, water repellents, flame retardants and many paper products to name a few.

A study published last year by Curtis Gubb et al of Birmingham University identified Nitrogen dioxide (NO2) as another significant pollutant both in outdoor and indoor environments. Exposure to the chemical is linked to serious respiratory illnesses, decreased lung function and airway inflammation.

NO2 is a key pollutant in towns and cities as it is a component of diesel fumes.

Although the chemical is not found in houses to the same extent, it is generated by the likes of fires and stoves and, critically, it remains and builds up indoors.

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The better insulated the house or flat, the more serious the problem.

Ironically, draughty old houses are much safer, but don’t worry, I’m not suggesting we should rip out the insulation and replace the double glazing with heat-releasing windows. Get some houseplants to help mitigate the problem.

Most of the plants we grow, such as ivy, peace lily and orchids, help improve air quality, especially when looked after properly.

The Herald: Houseplants

Researchers found that healthy plants worked much more efficiently and the more polluted the atmosphere the more they managed to clear it.

Plants require suitable light levels and should be regularly watered to grow well.

Leaves do much more than photosynthesise: they absorb many of the toxic chemicals, so the healthier the plant the more efficiently it will work.

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And give the leaves an extra hand by wiping off any accumulated dust and occasionally spraying down in the sink or tub.

Micro-organisms in roots and soil are also important so by adding a little home compost or even topsoil, you would inject many valuable micro-organisms to the commercial compost, as well as providing more feed for the plants.

PLANT OF THE WEEK

The lichen Cladonia coniocraea grows on wood and stone. It’s found in the Glasgow Botanic Garden on the bark of several tree species and on mossy stones. Vibrantly green after rain, it looks grey-green when dry. It’s tolerant of sulphur dioxide pollution, but dislikes phosphorous and nitrogen.

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