Dracaena. Pic by Linda Kiscellus__________
While the snows of winter are blowing around us, the focus of Illinois Landscape Contractors Association ( ILCA ) this month turns indoors. Did you know that plants can play a vital role in your health in your home and office?
Airborne pollutants
Studies by NASA over the past 20 years repeatedly show that houseplants are remarkably efficient filters of common and dangerous pollutants. This came about from their seeking ways to make closed spaces on the moon or Mars more livable. The studies concentrated on three main airborne pollutants: benzene, trichloroethylene and formaldehyde.
Benzene is a common solvent used in gasoline, oils, paints, plastics and rubber. Although it is being used less in the industry, Benzene is also used in the manufacture of detergents, pharmaceuticals and dyes.
Trichloroethylene ( TCE ) is used in many industries from dry cleaning to the printing process where certain inks contain TCE. Typical paints, lacquers, varnishes and adhesives also contain TCE.
Formaldehyde is still the most commonly found material of the three chemicals. It is typically present in nearly all indoor environments. Particle board and pressed-wood products as well as urea-formaldehyde type insulations are the most common sources. Also, consumer paper products like grocery bags, waxed paper, facial tissues and paper towels are treated with urea-formaldehyde resins. Many household cleaning agents, wrinkle resisters, water repellents, fire retardants and adhesive binders used in floor covering and carpet backing also contain formaldehyde.
More pollutants
Other common indoor pollutants such as asbestos, radon, lead and carbon monoxide that are emitted from furnishings ( fabrics, carpet, wall coverings, etc. ) , office equipment and other building materials were also researched. One study found that the right plants in the right place reduced indoor air pollutants by as much as 87 percent.
Office equipment and pressboard furniture are known to emit toxins into the air. Plants help filter breathing zones when placed in an office worker's personal space at the rate of one per seven feet of cubic space or approximately two per 100 square feet of floor space. Dutch researchers report that individuals working at computer monitors for more than four hours per day with plants in their workspace reported feeling better and more productive than their colleagues who had no plants at their desks.
Plant selection
According to the studies, the plants that are most effective at filtering indoor air are Aglaonema ( Chinese evergreen ) , Spathiphyllum ( Peace-lily ) , Syngonium ( arrowhead vine ) , Hedera ( English ivy ) , Dracaena ( cornplant ) , and Scindapsus ( Devil's ivy ) . Flowering plants, such as mums, azaleas, gerbera daisies, cyclamen and even tulips help clean the air for short periods of time. Philodendrons and spider plants were found to be the most efficient in the removal of formaldehyde. Gerbera daisies and chrysanthemums were found to be effective in the removal of benzene, a known carcinogen.
Plants will do little, if anything, to filter tobacco smoke in the air.
Additional benefits
Another benefit described in studies done in Great Britain is the perception that homes or offices featuring interior plantings were more expensive, felt more welcoming and provided a more relaxing environment.
Some studies challenged the rate of effectiveness of plants as air filters and point out that moist soils can also be a place for molds or other allergens to multiply. If reducing moisture in an area is a concern, the air filtering benefits of plants may be offset by this need. Most homes in northern climates benefit from increased air moisture levels during winter months.
Indoor plant care
Like any garden, the indoor garden of houseplants needs care and attention. Water houseplants when the soil becomes dry to the touch. If the container isn't overly large, you can give it the 'lift' test: Lift the container to determine its weight. If it is heavy, the soil probably contains sufficient moisture. If it is very light, it is dry and needs a good watering.
It is also a good time to inspect plants for signs of insects or other problems. Just as in the outdoor garden, indoor plants that experience watering stress as a result of too little or too much water are more susceptible to disease and pest problems.
Most houseplants will benefit from a monthly feeding of a balanced fertilizer designed for houseplants.
Choose plants according to their light and moisture requirements, as well as their suitability to the environment you can provide. Purchasing tropical plants from a reputable greenhouse or garden center that specializes in tropical plants can help ensure a good match. Bringing photos of the interior space you wish to enhance helps in proper selection.
Plants in the home or office can greatly enhance the design and a visitor's perception of the environment. For additional help, interiorscape professionals are trained in creating indoor landscapes and are a valuable resource when incorporating plants into your interior. The same principles of design that apply to exterior landscapes determine success indoors as well.
For information about ILCA and member landscape contractors and garden centers call 630-472-2851 or e-mail information@ilca.net . Contact Lenore Dupuis at 847-272-9542 or at lkdpr@aol.com .
Copyright, 2007, Illinois Landscape Contractors Association
