Have you ever noticed that when you walk into the home of someone who keeps a lot of plants, you feel just a little bit calmer? Researchers1 who evaluated the effects of indoor plants on 24 young male adults found active interaction with plants reduced their physiological and psychological stress. Participants were left feeling comfortable and soothed.
Research has also demonstrated that university students taught in classrooms where tropical plants were present gave higher ratings to both the course and the instructor.2 One group is so convinced of the power of plants to reduce stress that they’ve made it a mission to bring plants into every classroom.3
Plants may sharpen your attention capacity,4 reduce sick leave and improve productivity.5 They may also speed recovery from surgery.6 In a study from the University of Exeter, researchers found adding greenery to an otherwise austere office could increase productivity by 15%.7
While each of these benefits improves your overall health, you’ll also likely benefit from the specific improvements that snake plants make in reducing indoor air pollution.8
Many are aware that outdoor air pollution carries dangerous risks. Some of the more common pollutants include particulate matter, nitrogen dioxide, carbon monoxide,9 formaldehyde and volatile organic compounds10 such as benzene.11 The American Lung Association says these common pollutants trigger asthma episodes and shape how children’s lungs develop.
The World Health Organization says air pollution is a major environmental risk to health. In 2016, WHO found that outdoor pollution caused 4.2 million premature deaths around the world.12 While dangerous, indoor air quality can be just as destructive. According to the Environmental Protection Agency, some pollutants are two to five times higher indoors.13
Those who are most vulnerable are the young, old and those who are suffering from cardiovascular or respiratory disease. In the past decades, concentrations of some pollutants have risen as buildings have become more energy efficient. Some buildings also lack sufficient mechanical ventilation and use a rising number of synthetic building materials.14
The concentration of indoor pollutants rises when man-made chemicals and other substances are released in or near your home. A number of common sources, such as household cleaning products, building materials, pesticides, air fresheners and space heaters are responsible.15
These pollutants have both short- and long-term health effects. Short-term exposure16 may increase your risk for allergy reactions including worsening asthma, headaches, fatigue and dizziness. Long-term health conditions may include acute lung infections, chronic obstructive lung disease, lung cancer,17 high blood pressure and diabetes.18
In this short TED talk environmental activist Kamal Meattle, CEO of Paharpur Business Centre in New Delhi,19 spoke about how he successfully improved the indoor air quality in his business using three plants, of which a snake plant was one. He had a bad reaction to the air pollution in New Delhi and was told his lung damage was killing him.
After learning about a NASA20 study in which several plants were analyzed for their ability to remove toxins and add oxygen, he added three common green plants to his building and realized significant results. He used areca palm (Chrysalidocarpus lutescens), snake plant or mother-in-law’s tongue (Sansevieria trifasciata) and money plant (Epipremnum aureum).
Meattle conducted his studies in his 20-year-old, 50,000 square-foot building with 1,200 plants for 300 occupants. There was a 42% probability the occupants’ blood oxygen level would rise by 1% when they stayed indoors for 10 hours,21 a significant feat in New Delhi that ranks as the world’s most polluted city.22
According to Meattle, the Indian government compared the health conditions of occupants in his buildings to those in other buildings and found there was a reduced incidence of eye irritation by 52%. Respiratory symptoms were reduced by 34%, headaches were lowered 24% and lung impairment went down by 12%.23
The snake plant converts CO2 into oxygen during the night hours, which has earned the plant the nickname the “bedroom plant”. To supply enough oxygen in his building Meattle found they needed six to eight waist-high plants for each person.24
A common byproduct of respiration is carbon dioxide. Indoor levels that rise may increase the chance that those living and working in confined spaces will suffer from declining performance and learning. Rising levels of CO2 also directly affect cognitive skills and productivity.25
In one study published by the International Conference on Chemical, Metallurgy and Materials Science Engineering, researchers evaluated the ability of a snake plant to absorb carbon dioxide in the office. They found that in an office with 360 M3 airspace and three staff people where four snake plants were used, the snake plants absorbed 22.93% of the carbon dioxide.26
In addition to adding oxygen and removing CO2 in the environment, NASA also demonstrated the ability the snake plant has to reduce the levels of trichlorethylene, benzene and formaldehyde.27 When the plant leaf surface area was 2,871 square cm, the plant removed 31,294 mcg of formaldehyde and 28,710 mcg of benzene. A plant with 3,474 square cm of surface area removed 9,727 mcg of trichloroethylene.28
Trichloroethylene is a nonflammable liquid used as a solvent to remove grease. However, it’s also found in paint removers, spot removers and adhesives. Although not found naturally in the environment, the snake plant is able to remove trichloroethylene from the air. It’s classified as a volatile organic compound and is carcinogenic to humans with a higher evidence for kidney cancer.29
Benzene is among the top 20 chemicals commonly used and is found in plastics, synthetic fibers and resins. Manufacturers also use benzene to produce rubber, detergents, pesticides and drugs. It’s classified as a hydrocarbon and is considered a volatile organic compound. This known human carcinogen commonly affects the blood, immune system and nervous system.30
At room temperature, formaldehyde is a colorless gas with a distinct smell. It’s classified by the EPA as a “probable” carcinogen, but the International Agency for Research on Cancer classifies it as carcinogenic to humans. It is a volatile organic compound that affects your skin, digestive tract, immune system and respiratory system. It’s found in the production of food, paper, antiseptics, cosmetics and resins.31
Each of the substances the snake plant is known to affect in your indoor environment are dangerous to your health. However, as Meattle commented in his video, the addition of plant life to your home can create a healthy environment for you and your family without much effort.
The snake plant might be one of the easiest, low maintenance houseplants to keep as it may thrive in full sun or full shade. It’s drought-resistant and also does well when you water it consistently. The plant is found in most nurseries and one may be propagated from another. It’s a hardy plant with stiff upright leaves that range in height from 1 foot to 8 feet.32
Although most are called mother-in-law’s tongue, that variety typically has a yellow border along the leaves. The plant is a member of the Asparagacea family, which includes asparagus. It’s native to West Africa and also goes under the names viper’s bowstring hemp and St. George’s sword.33
It is an ideal plant for containers around your home, but thrives outside in Hardiness Zones 9 to 11. The snake plant may adapt to full sun conditions and will survive in the shade but it prefers indirect, steady light.34 When potting, use well-draining potting soil, avoiding those low in peat because they don’t drain well. Soil intended for cactus is a good choice.
Don’t allow the roots to sit in water as it increases the risk of root rot and fungus.35 The soil should dry between watering and during the winter months it should be watered less frequently. Protect your plants from drafts and keep it away from the air conditioner and heating vent.
The plant does not need any pruning36 but may require repotting each year as it grows rapidly. When repotting, always use fresh soil.37 The snake plant makes a beautiful addition to your home but is also toxic to small children and pets.
Keep the plant out of reach and if you see signs of toxicity, such as excessive salivation, nausea or diarrhea, seek medical attention for your child or pet.38 The plant sometimes triggers allergic contact dermatitis but it’s usually only toxic when ingested.39
The plant comes in a number of different varieties, heights and sizes. Although it improves your indoor air quality, snake plants also add a unique flavor to your decorating. Since the plant is so versatile you can choose to decorate your patio during the summer and bring it in during the winter. If you do choose this option, be sure to slowly harden the plant in the spring before it’s left out day and night. Varieties of snake plants include:
- Sansevieria trifasciata Black Gold — This cultivar has leaves growing relatively straight with light yellow to gold edges and dark green centers.40
- Sansevieria trifasciata Futura Robusta — This is the shortest of the snake plants with silvery green leaves.41
- Sansevieria trifasciata Cylindrica — This unique variety has round shaped stiff leaves that may reach several feet in height. The leaves resemble bamboo42 and arch outward from the center.43
- Sansevieria trifasciata Twist — This variety grows to about 14 inches, making it perfect on a table or as a hanging plant. The leaves are twisted and striped horizontally with yellow edges.44
- Sansevieria trifasciata Whitney — This dwarf variety has dark green centers bordered by silver green edges.45
One way to have increase the number of snake plants in your home is to propagate them. The plants are popular and easy to grow, so you may have a few friends with varieties you don’t already own. There are four different ways to propagate your snake plant.46
Anytime one gets too big for the pot, you can either choose to repot it in something larger or split it and divide the plant. Remove the plant and use a knife to cut the roots and separate the stalks. Once it’s repotted and the roots covered with soil, mist the plant with water.
Another option is to pull out the young shoots, or rhizomes, which are often found below the soil when you’re repotting. Pull the shoots apart by the roots. You can plant each one individually in a separate pot or you can plant several of the largest ones together in a large pot.
You can also propagate the plants by taking a cutting of a leaf close to the base. The cutting can either be placed in a fresh pot of soil or in a vase with water. If you choose water, change it every few days and then once the roots begin to develop, pot in some fresh soil.47