Green plants enliven our homes, providing color and texture to soften living spaces. This kind of “green living” is increasing in popularity as science catches up with what gardeners have known all along—plants can help keep you healthy, make you happy and boost your creativity.
“Growing plants have a calming effect that can help lower blood pressure, reduce levels of stress hormones and keep heart rate at a healthy level,” says Bruno Cortis, MD, cardiologist and assistant professor of Medicine at Rush University in Chicago.
This explains why it’s not just for aesthetic purposes that commercial buildings often include living plants in their designs and that interior decorators recommend including as many plants as space allows in your home décor. Fortunately, it doesn’t take a super-green thumb to grow many species indoors.
Living Air Filters
Almost every residential or commercial space contains air contaminants. They include ammonia (household cleaning products, photocopiers, printers), formaldehyde (carpets, draperies, some furniture, paper towels, gas stoves), benzene (printer ink, paints, floor coverings) and xylene (caulking compounds, paints, wall coverings).
A landmark study conducted by the National Aeronautics and Space Administration (NASA) in the 1980s tested 50 houseplants for their ability to remove various toxic gases from the air in enclosed spaces, similar to those found in energy-efficient homes. Researchers discovered that common species could remove up to 87% of airborne toxins in a 24-hour period. During the process of taking in oxygen from the air, plants remove harmful chemicals that can cause respiratory problems, headaches, drowsiness and irritated eyes.
If you have the room, larger plants such as dracaena, bamboo palms, golden pothos, rubber plant, Norfolk Island pine, schefflera, spider plant and ficus can be very effective. Even small plants, such as chrysanthemum and gerbera daisy, are useful in removing chemical vapors from the air while perking up a room with colorful flowers.
In fact, while most plants absorb carbon dioxide and give off oxygen during the day, gerbera daisies conduct this process at night so a pot in your bedroom may help improve sleep. (B.C. Wolverton, PhD, environmental engineer and a primary researcher on the NASA study, discusses specific plants in How to Grow Fresh Air (Weidenfeld & Nicolson).)
Air dries out fast in enclosed spaces, especially if homes and offices are artificially heated or cooled. But plants can act as a natural humidifier. “By placing plants in a saucer with pebbles and water, humidity around the plant is increased,” says Kyle Wallick, botanist with the US Botanic Garden in Washington, DC. Studies show that when plants are placed in offices, workers experience a 25% drop in tiredness, coughing, sore throats and other cold-related symptoms.
Broad-leaf specimens such as philodendron, peace lily and English ivy release the most moisture into the air. Boston fern humidifies the air by releasing water vapor in exchange for atmospheric pollutants. Cyclamen and kalanchoe humidify while adding color during the drab winter months.
Plants have a calming effect—one reason they often accompany significant life events such as weddings, funerals and hospital stays. Plants lower anxiety levels and help people recover from mental exhaustion faster.
“When we look at plants, we focus attention on something other than what worries us or causes physical pain,” says Cortis. “Plants bring a spiritual quality, a sense of unity with the world, and help us adjust to the cycle of life.” Studies have shown that hospital patients facing gardens recovered more quickly than those facing a wall or parking lot. “An inspiring environment helps heal,” Cortis adds.
Easier breathing and clearer thinking are benefits of plant transpiration—the process by which plants take in carbon dioxide we exhale and subsequently increase oxygen in the air. “All organs of the body, especially the heart and brain, work better with high levels of oxygen,” says Cortis, author of Heart and Soul: A Psychological and Spiritual Guide to Preventing and Healing Heart Disease (Villard).
You’ll think better and stay focused longer with an English ivy plant nearby because it cleans the air of common office chemicals. Flowering plants such as African violets, lilies, bromeliads or cut flowers can boost dopamine, a brain chemical associated with better mood and information processing.
An additional benefit: Multiple houseplants in a room help reduce noise level, which promotes a calmer environment, Cortis says.
Worried about all those plants setting off a round of sneezes, sniffles and watery eyes? Most pollen allergies come from wind outdoors, which usually isn’t an issue with indoor plants, says Wallick. Mold spores are also generally airborne and unlikely to be a problem with houseplants. If you have allergies to pollen or mold, consult your healthcare provider about specific plants to avoid.
Some people shy away from plants for fear of not being able to keep them alive and thriving, and it’s true that some plants require a greener thumb than others. However, you can find houseplants that will foster your well-being without their care becoming an all-consuming hobby.
Plants do have some basic needs. The first one is light; the more south-facing a window, the more light it receives. Plants that don’t need a lot of light include philodendron, pothos and peace lily. The cast-iron plant even boasts of its toughness in its name, surviving not only low light but also low humidity, temperature variations and overall neglect. Plants with colorful leaves may not need bright conditions to live, but will often revert to green when the light is low.
Plants require different levels of humidity in the air as well as whether they prefer their roots on the moist or the dry side. Cacti and other succulents are known for preferring arid conditions. The Boston fern and African violet love high humidity, although the first prefers damp soil while the second needs well-drained soil for best results.
Temperature is the other major consideration for plant growth, keeping in mind that none of them like cold drafts or blasts of hot air from radiatiors. English ivy prefers cooler conditions, while dracaena and rubber plants like things kept a little warmer.
Fill your home and workspace with as many plants as you can. They’ll help cleanse the air and relax your mind.