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Plants as Air Purifiers

In the winter we spend most of our time indoors. The cleansers and chemicals we use along with the other materials in our houses and workplaces can actually pollute the air we breathe. We can improve our indoor air quality by bringing in houseplants which absorb pollutants.

Plants in the home or office can filter out toxins, stale air, pollutants, harmful viruses, and mould spores. The more indoor plants you have, the cleaner your air will be. But you don't need to turn your home into Jurassic Park.; all you need is two or three plants for every 100 square feet of living space.

Some homes and offices have indoor air quality problems caused by Volatile Organic Compounds (VOC’s). Some of the causes are; photo copiers, office furniture, computers, printers, carpets, glues, and white out. Many cleaning agents may also contribute to poor air quality. All plants clean the air. In the process of photosynthesis the plants take in the carbon dioxide we exhale and give off oxygen. A NASA study revealed that some plants have the ability to filter out Volatile Organic Compounds.

A Few Tips to Keep your Green Machines Well Tuned to do their Job Efficiently

WATERING:  The rule of thumb when watering indoor plants is to water only when the top inch of soil becomes dry. Give the plants a good soaking, enough so that water pours from drainage holes. Don't water again until soil surface becomes dry. This watering technique helps to leach fertilizer salts out of the soil. Salt build-up is often responsible for browning leaf tips on many plants, especially palms and spider plants. 

Over-watering indoor plants can cause problems. Not only can you kill the plant, you also invite mold to form on the top of the soil. Worse yet, soggy soil attracts fungus gnats, irritating little flies that feed on moist, decaying potting soil. In high humidity climates such as ours it is best to maintain house plants in a potting soil that is not too heavy with peat moss. 

BATHING:  Once a month give your plants a good hosing down, either outside or in the shower. Be sure to wash the undersides of the leaves as well.

Removing household dust from the foliage allows the plants to "breathe" better. It also helps prevent infestations. Palms especially need their leaves washed regularly to deter spider mite infestation. 

DON'T SHINE THEM:   Do not use leaf shines of polishes to brighten up plants. These preparations clog the stomata, or leaf pores. Plants need to breathe in order to photosynthesize. If you keep plants well-fed and bathed they will produce their own natural glow. 

DRAFTS:  Do not place indoor plants, especially palms, near drafty doors or windows. Pests like aphids, spider mites and mealy bugs easily blow in with the wind. 

INSPECT REGULARLY:  Every other week or so take a look at the undersides of leaves and the growing tips of your plants. Spider mites cause mottling or stippling of leaves. Aphids congregate at the growing tips and undersides of leaves.  If plants begin to develop stickiness on the leaves suspect aphids or scale.  A regular spray of work juice making sure you get under the leaves should do the trick

Source:   Teresa Rutherford - Compost Happens

FERTILIZING: (master gardeners recommend . . .) The fertilizing program is directly related to light intensities, and, hence, growth levels.  When first purchased, because of a relatively high nutrient level in the growing media, plants should not require any fertilizer for three months (unless obvious nitrogen deficiencies occur).  After this time use a 20-20-20 or 15-15-15 fertilizer at the recommended rate during high light intensity periods (i.e. March to October) with a reduction of the application by one-third to one-half during the winter months.  


For full article that includes a list of air improving plants that remove three of the most common indoor air pollutants see the attached pdf.
Dinah Wilson,
Nov 9, 2011, 5:30 AM