Gardeners may be finishing up some fall cleanup in perennial borders, straightening their garden sheds and cleaning tools, but there's no doubt about it -- the gardening season outdoors is coming to an end. Gardeners can keep their green thumbs occupied while improving the air we breathe by growing houseplants inside.
Carbon monoxide and radon may be the first things we consider when we think of air pollution indoors, but there are other sources that make the air indoors unhealthy to breathe. Volatile organic compounds, or VOCs, occur as off-gasses from common household products like hair sprays, household cleaners, paints and even furniture and carpeting.
Houseplants help clean the air. Plants take in pollutants through the microscopic openings in their leaves. These pollutants then move through the plant to its roots, where microbes break down the pollutants into food for themselves and the plant.
Even gardeners who have a history of filling compost bins with the remains of unsuccessful attempts at growing houseplants can reap their air-cleaning benefits if they select these houseplants, which are nearly impossible to kill:
Aloes have distinctive, thick and fleshy, elongated leaves edged with little spikes that fan out from the center of the plant. Position them in a sunny window and let the well-drained potting mix dry between waterings. Aloes absorb carbon dioxide and give off oxygen during the night, making them an ideal choice for bedrooms.
One of the best at purifying the air, peace lilies feature glossy, lance-shaped, dark green leaves on arching stems. Spoon-shaped flowers rise from the center of plants. Peace lilies are adaptable to varied light conditions, but require consistently moist potting mix.
Sansevieria, commonly called mother-in-law tongue or snake plant, has upright, leathery, sword-shaped leaves edged with yellow or white. It is among the easiest of all houseplants to grow. It grows just about everywhere, tolerating light situations from sunny to dim. Let the potting mix dry before watering. Its transpiration rate is so low it can go for weeks without water. Snake plant is another houseplant that absorbs carbon dioxide and releases oxygen at night.
Dieffenbachia features large arching leaves, often marbled with creamy-white, that grow out of a thick cane-like stem, giving this houseplant a tropical flare. A good choice for removing VOCs from the air, it grows as tall as 6 feet. It prefers low to medium light and evenly moist potting mix. Dieffenbachia gets its common name -- dumb cane -- from the toxic sap in its stems and leaves that cause numbness of the tongue when chewed by people or pets.
Commonly called spider plants for the spider-like plantlets that dangle from mother plants, they are beautiful in hanging baskets. The variety most often available has green leaves with white stripes down the center. Give them a spot with bright light and water them with distilled water, if your water is fluoridated, to prevent brown leaf tips. Misting will increase humidity around plants. Spider plants are very proficient at removing toxins from the air.
A ficus enjoys summer on my front porch and then moves indoors to spend the winter. Mine is a single trunk tree but plants are available in multi-stem and braided-stem forms, too. They may drop some of their glossy green leaves as they adjust to a new environment but will quickly recover. Ficus trees prefer medium to bright light and their potting mix kept slightly moist.
These are just a small sampling of easy-to-grow houseplants that not only add living decor to your home, but also keep your green thumbs from suffering from gardening withdrawal, and clean the air you breathe indoors while you are busy planning next year's garden.
• Diana Stoll is a horticulturist, garden writer and the garden center manager at The Planter's Palette in Winfield. She blogs at gardenwithdiana.com.