One big concern regarding living in Bangkok with our young family is the air pollution. In addition to getting a good air purifier for our living spaces, we looked into plants to place around our condo that help clean the air. Here are 5 tropical varieties that absorb air particles and carbon dioxide, and release oxygen. They can be grown indoors or outdoors — and all are relatively low maintenance.
1. Spider Plants (Thai: เศรษฐีเรือนนอก) help remove carbon monoxide and other toxins from the air, and they have been named by the NASA Clean Air Study as one of the plants that are most effective at ridding the air of formaldehyde. They can be grown inside or outdoors, but in well-drained soil and without exposure to too much direct sunlight, otherwise they can get burnt. Water well but let them dry out in between waterings to avoid root rot.
2. Snake Plants (Thai: ลิ้นมังกร) come in regular and dwarf varieties, and are easily identified by their spiky, stiff and dense stands. In Bangkok, they thrive both outdoors and indoors, requiring low light and irregular watering. Don’t overwater as they can easily rot. Snake plants are slow growing, but effective at absorbing nitrogen oxides and formaldehyde; they also release oxygen at night and are thus suitable for placement in your bedrooms.
3. Boston Ferns (Thai: เฟรินบอสตัน) clean the air of formaldehyde and xylene. Ideally, place them indoors or outdoors in areas of high humidity and some direct sunlight. They are pretty easy to care for, but like to stay in moist soil and have their leaves misted regularly. The added benefit of these plants is that they can act as humidifiers, restoring moisture in the air — good for those who suffer from dry skin.
4. Areca Palms (Thai: ปาล์มหมาก) are one of the best air purifying plants when it comes to general air cleanliness. According to the NASA study, these palms specifically filter xylene and toluene from the air. They are good as indoor plants and need to be watered often enough to keep the soil slightly damp. They can also grow quite tall; at 1.8 meter tall, the plant will transpire 1 liter of water per 24 hours, which also makes it a natural humidifier.
5. Golden Pothos (Thai: พลูด่าง; note: toxic for pets if ingested) are especially hardy, and commonly seen around Bangkok in both indoor and outdoor settings. They are good for improving indoor air quality, and can be placed in any room as they tolerate a variety of light conditions. Pothos plants do well when their soil is allowed to dry out between waterings; if you notice the leaves turning brown or are wilting, water them more often.
How many plants would you need?
The NASA study recommends 15 to 18 plants in pots 15 to 20 cm in diameter (about 6 to 8 inches) to clean the air in a 160 square metre (roughly 1,800 square foot) home. That comes out to around one plant per 9 square meters (100 square feet) of floor space.