Houseplants are a relatively easy and inexpensive way to add color and life to your interior landscape in the dead of winter; but in addition to brightening your home, houseplants can offer some health benefits.
When NASA was doing research on how to keep the air pure in future space stations, they discovered that houseplants and blooming plants can fight pollution, with the ability to scrub substantial amounts of harmful gases, such as benzene, formaldehyde and trichloroethylene out of the air through photosynthesis. In addition plants absorb some chemicals and render them harmless in the soil. Benzene, formaldehyde and trichloroethylene are the three worst offenders when it comes to indoor pollution because they can be found in a lot of new home products such as synthetic carpeting, fabrics, laminates and plastic coated wallpapers.
It is probable that all houseplants are beneficial to air quality to some degree but only certain ones were tested; some of them are more effective on formaldehyde and others on benzene but none of the plants were any good at removing tobacco from the air. NASA researchers recommend 15-18 good-sized houseplants in 6-8 inch diameter containers to improve the air quality in an 1800 square foot house. This may seem like more plants than you want to care for but any number will help to improve your indoor air.
There are two challenges to growing houseplants in Minnesota in the winter–light and humidity. Different plants have different light requirements, but when they are light-deprived they can show similar symptoms; they may grow spindly, shed older leaves, variegated leaves may turn to solid or flowering plants may fail to produce buds. There are three factors to determine when evaluating light: intensity, which is the brightness; duration which is the number of hours of sunlight in a 24 hour period; and quality, which is the wavelength or color of the light (plants use red and blue light to produce food).
In Minnesota winters light intensity and duration are limited, so it is imperative that you place plants to get the needed amount of light. Luckily, the plants studied by NASA that improve air quality have a variety of light requirements. Low light means no direct sunlight such as in a north window in the winter; NASA tested plants that have low light requirements include red-edged dracaena (Dracena marginata), cornstalk dracaena (Dracena fragans ‘Massangeana’), Chinese evergreen (Aglaonema modestum), golden pothos (Epipiremnum aureum), and heartleaf philodendron (Philodendrdren scandens ‘oxycardium’). Medium light can be provided by a well-lit east window or a few feet from a west facing window. Plants that do well in medium light include ferns, begonias and African violets. Plants such as Benjamin ficus require high light which is provided in a south or southwest window.
Humidity is another challenge to growing houseplants in Minnesota. Heating our homes tends to leave them dry, especially if we have forced air heating. Plants that are losing moisture through their leaves faster than they are taking it up through their roots can be identified by browning leaf tips, yellow leaf margins, shriveling, and wilting or even bud drop. Plants with too much moisture can experience root rot, mold or mildew, therefore water only when necessary, not on a schedule. You can also use a room humidifier, which is good for you as well as your plants.
Keep your plants away from drafts and radiators — both of which will dry them out. Use a good soil mix that will hold water longer and keep the temperatures a little lower in your home.
Try placing your plants on a tray of pebbles covered with water and group plants together so they can benefit from the humidity generated by each other. Place your plants in humid areas in your home such, as in the bathroom, near the kitchen sink or over an aquarium; just be sure that they are receiving adequate light.
Whatever houseplants or how many you may choose to grow, they can not only perk up your interior landscape but your psyche as well.