The lineup

Houseplants considered to be great toxin removers by NASA and the Plants for Clean Air Council:

• Areca palm (Chrysalidocarpus lutescens): Top-rated for removal of chemicals.

• Lady palm (Rhapis excelsa): One of the easiest houseplants to care for.

• Bamboo palm (Chamaedorea seifrizil): One of the best for adding humidity to dry air.

• English ivy (Hedera helix): Grows in a variety of environments.

• Boston fern (Nephrolepis exaltata: One of the best as natural humidifier.

• Peace lily (Spathiphyllum spp.): Boasts a high transpiration rate; blooms indoors.

• Corn plant (Dracaena): Many varieties are considered beneficial.

• Mother-In-Law’s Tongue (Sanservieria): Photo on D4.

• Philodendrons and Schefflera are considered fresh air plants, however, they are listed as being toxic to children and pets.

Gerber daisy: Long bloom indoors, high transpiration rate.

Houseplants, like everything else, wax and wane in popularity. Beyond the trends, however, houseplants offer many benefits for people.

Many commonly used synthetic materials release gases into our homes. It wouldn’t take long to make an extensive list of products we use and enjoy daily that release gases: everything from our easy-care carpeting to our laundry aids.

In the late 1980s, the National Aeronautics and Space Administration concluded a study on the benefits of indoor plants and their ability to help purify the air.

Three common pollutants — formaldehyde, benzene and trichloroethylene — were absorbed by plants in sealed test chambers. The toxins were taken in by the plant’s leaves and translocated to the root system, where soil microbes broke them down for food. Like microscopic robots these soil helpers gobbled up the toxins that filled the air. Isn’t nature great?

I know that many volatile chemicals have been outlawed, but there is probably a whole new “crop” that lingers in our homes.

Regardless of the uncertainties of the study to remove toxins, (how many plants to use and where they should be placed) the addition of houseplants can help improve air quality.

On a very basic level, houseplants play an important role in helping to raise the humidity level. Through a process of transpiration, water evaporates through plant leaves. Many recommend a humidity level for a home between 35 and 65 percent — a level that is probably hard to attain in our Central Oregon homes without a little help.

Dry air irritates sensitive membranes in the nose. In addition to acting as an aid in raising the humidity level, houseplants also exchange the carbon dioxide we exhale with life sustaining oxygen.

Dr. B.C. Wolverton, a NASA researcher, tested 50 houseplants for their ability to remove toxins from indoor air and published the results in his book, “How to Grow Fresh Air,” published in 1996.

Stress relievers

Houseplants are also valuable in the work place as stress relievers. Studies from Texas State University and Agricultural University of Norway, among others, have been conducted that indicate productivity increases where plants are allowed in the workspace. Blood pressure may be lowered while some workers feel more attentive to their tasks when plants were present.

For best results, keep the plants’ lower leaves trimmed to expose the soil root zone. This allows more of the organisms to have easier access to the toxic gases. Arrange the plants throughout your air space instead of grouped all together. Be mindful of the plants’ needs and use fertilizer.

— Reporter: