Snake plants filter certain toxins from the air, produce oxygen at night, and serve as low-maintenance indoor greenery that may offer modest mental health benefits. They’re one of the most popular houseplants in the world, and their reputation largely traces back to a 1989 NASA experiment. But what a snake plant actually does in your home is more nuanced than the headlines suggest.
Air Purification: What’s Real and What’s Overstated
The snake plant’s claim to fame comes from NASA research showing it can remove volatile organic compounds from the air, including formaldehyde, benzene, xylene, and trichloroethylene. These are chemicals found in household products like paint, cleaning supplies, and synthetic furnishings, and long-term exposure to them has been linked to cancer and respiratory issues. In a sealed lab chamber, snake plants absorbed these compounds effectively.
Here’s the catch: your home is not a sealed lab chamber. A 2019 analysis by researchers at Drexel University reviewed the body of potted plant research and calculated something called a “clean air delivery rate” for houseplants. In every case, the rate at which plants removed pollutants was orders of magnitude slower than the normal air exchange that happens in buildings through ventilation, HVAC systems, or simply opening a window. To match the air-cleaning power of basic ventilation, you would need between 100 and 1,000 plants per square meter of floor space.
So while the chemistry is real, the practical impact of one or two snake plants on your indoor air quality is negligible. The plants do absorb small amounts of pollutants. They just can’t compete with the air already cycling through your home.
Nighttime Oxygen Production
Most houseplants absorb carbon dioxide and release oxygen during the day through photosynthesis, then reverse that process at night. Snake plants are one of the few species that continue converting CO2 into oxygen after dark. They do this through a type of photosynthesis called CAM (crassulacean acid metabolism), which evolved in plants from dry climates to conserve water by keeping their pores closed during the day and open at night.
This makes the snake plant a popular choice for bedrooms. The amount of oxygen one plant produces overnight is small, so you won’t notice a dramatic difference in how you sleep. But if you’re choosing between houseplants for a bedroom, the snake plant’s nighttime oxygen release gives it a genuine edge over most alternatives.
Mental Health and Stress Reduction
A 2022 scoping review published in Environmental Research looked at all available epidemiological studies on indoor plants and mental health. Every study included in the review pointed in the same direction: having indoor plants was associated with reduced stress, fewer depressive symptoms, and fewer negative emotions. The evidence base is still small, and the researchers noted that the overall body of epidemiological research on this topic remains limited. But the consistency of the findings across different study designs is notable.
This isn’t unique to snake plants. Any indoor greenery appears to offer these benefits. The advantage of a snake plant specifically is that it’s almost impossible to kill. It tolerates low light, irregular watering, and temperature swings that would destroy more delicate houseplants. That durability means you’re more likely to keep it alive long enough to enjoy whatever psychological lift it provides, without the stress of high-maintenance plant care working against you.
Where to Put a Snake Plant
Snake plants thrive in indirect light but tolerate everything from bright sun to dim corners. They prefer their soil to dry out completely between waterings, which typically means watering every two to six weeks depending on the season and humidity. Overwatering is the most common way people kill them.
Bedrooms are the most recommended placement because of the nighttime oxygen production. Offices and living rooms work well too. Snake plants grow vertically and take up minimal floor space, making them practical for smaller rooms. They come in varieties ranging from six inches to several feet tall, so you can match the plant to your space.
Toxicity to Pets and Children
Snake plants contain saponins, a natural chemical compound that’s toxic to cats and dogs. If a pet chews on the leaves, the most common symptoms are nausea, vomiting, and diarrhea. The ASPCA lists the snake plant (also called mother-in-law’s tongue) as toxic to both cats and dogs. The same compounds can cause similar gastrointestinal symptoms in young children who mouth the leaves.
The toxicity is generally mild, not life-threatening, but it’s worth placing the plant on a high shelf or in a room your pets don’t frequent. If you have a cat that chews on anything green, a snake plant is not the best choice for an accessible spot.