The indoor pollutants that affect health  are formaldehyde, Volatile Organic Compounds (benzene and trichloroethylene or TCE), airborne biological  pollutants, carbon monoxide and nitrogen oxides, pesticides and disinfectants (phenols), and radon.  These pollutants contribute to ‘sick building syndrome’, which causes symptoms ranging  from allergies, headaches and fatigue through to nervous-system disorders, cancer and death.

 

Through  studies conducted by NASA, scientists have identified  50 houseplants that remove many of the pollutants and gases mentioned above. NASA, with assistance from the Associated Landscape Contractors of America, conducted a two-year study directed by Dr. B.C. Wolverton, an environmental engineer from Picayune, Washington, and a research scientist for NASA for over 20 years. Dr. Wolverton’s study of the interaction between plants and air found that houseplants, when placed in sealed chambers in the presence of specific chemicals, removed those chemicals from   the chambers. He concluded that plants can clean  pollutants in homes, offices, factories and retail outlets.

 

Later, Wolverton expanded the study and assigned plants a rating from one to 10, based on a plant’s ability to remove chemical vapors or indoor air toxins, ease of growth  and maintenance, resistance to insect infestation, and the rate at which water  evaporates from the leaves. He summarized much  of his research in his book, “How to Grow Fresh Air – 50 Houseplants that Purify Your Home or Office.”

 

More information on this study as well as references and details on specific chemicals can be found on Dr. Wolverton’s website.

 

Top ten indoor  plants for removing formaldehyde, benzene, and carbon monoxide from the air:

2. Lady Palm (Rhapis excelsa)

The Rhapis are some of the easiest palms to grow, but each species has its own particular environment and culture  requirements. The “Lady Palm” is a durable palm species that adapts well to most interiors, preferring semi-sunlight and a temperature of 60-70 F (16-21 C). While the plant grows slowly, it can eventually  reach more  than 14 feet in height  with broad  clumps often  having a diameter as wide as they are tall.

 

In general, the plant is very resistant to insect infestations, though occasionally spider mites will attack a Lady Palm. These can usually be removed with soapy water  if caught soon enough. Other things to watch for include  a location that’s too dry: this will cause the tips of the fronds to turn brown and dry out.

 

To care  for your Lady Palm, water  generously in spring and summer, increasing the volume in winter if your plant is located in a warm, dry environment. Feed monthly with liquid fertilizer and enjoy the plant’s glossy leaves on graceful, arching stems.

 

3. Bamboo palm (Chamaedorea seifrizii)

The bamboo palm is another plant that scored very high in its ability to remove formaldehyde from the air. This plant also effectively removed benzene—an ingredient used to make dyes, lubricants, rubbers, and detergents—and trichloroethylene, an industrial solvent. Its lacy, green fans born on clusters of slender canes add humidity to any room, along with a tropical feeling.

Also called the “reed palm,” the bamboo palm prefers bright indirect light and a temperature of 60-70 F (16-24 C). A southeast window in a moderately warm room is the perfect location. New plants will lose of some interior foliage as they acclimate to indoor settings, but this is normal. Remove dead fronds, but don’t pinch out the tip of new stalks because this will slow or eliminate new growth. In terms of a growing medium, bamboo palms prefer a little sand added to their soil mix.

While this plant likes to stay uniformly moist, it doesn’t like to be over-watered or to sit in standing water. Water generously during the spring and summer when the plant is growing actively, pouring any leftover water from the drainage tray. In winter, water just enough to keep the root ball moist.
Indoor palms may attract spider mites, which can be controlled by spraying with a soapy solution. 

 

4. Rubber Plant (Ficus robusta)

The rubber  plant is especially effective at removing formaldehyde from indoor air. A favorite  since the Victorian era, the plant grows very well inside and tolerates temperatures as low as 40 F (5 C) for short periods. Its ideal temperature range  is 60-80 F (16-27 C).

 

While rubber  plants prefer semi-sunlight to semi-shade, they will tolerate dim lighting, making  them extremely easy to situate. Avoid direct sunlight, however, especially in summer. In dry, centrally heated rooms, watch for scale insects, spider mites, and thrips. Growing to a height  of eight feet with a spread of up to five feet, rubber  plants may also need  to be supported by a stake. Wear gloves when pruning, since the milky sap may irritate the skin.

 

5. Dracaena “Janet Craig” (Dracaena deremensis)

Rated as one of the best plants for removing trichloroethylene from the air, the Dracaena is also

 

one of the easiest houseplants to grow. The mature plant reaches 10 feet in height  with a spread of three  feet, and can live for decades if properly maintained.

These plants do best in indirect  sunlight coming from the east/west, or semi-shade. They can adapt to lower light levels if the watering is reduced. Keep the soil evenly moist and never let the plant get soggy. In the same way, avoid letting the root ball dry out completely. Water less frequently in the winter months. Mist frequently with warm water, removing any dead leaves. (Leaf tips will go brown if the plant is under watered but this browning  may be trimmed.) If possible, avoid fluoridated

water, since these plants can be sensitive to fluoride.

In spring and summer, feed with liquid fertilizer every two weeks. Refrain from fertilizing during the wintertime. Repot using a commercial potting soil every other  year. The plant’s ideal temperature range  is 60-70 F (16-24 C). The plant can survive in lower temperatures (as low as 50 F or 10 C), but the leaves may suffer, turning yellow. They are also susceptible to mites, scale insects, and

 

mealybugs—more so when the air is too dry. Keep humidity above  40% and remove insects when they appear with a wash of soapy water.

 

 

7. Dwarf Date Palm (Phoenix roebelenii)

Scoring  very high for its ability to remove airborne chemicals, the dwarf date  palm is especially effective at ridding the air of xylene, a common solvent ingredient. The plant is well suited to controlled temperature environments in offices and homes and will survive for decades if situated optimally.

 

Place  in semi-sunlight free from drafts with temperatures between 60-75 F (16-24 C). Provide adequate space, since this plant, although slow growing, will reach heights of 8-10 feet. But one caution: the dwarf date  palm should not be placed near children’s play areas because it has sharp, needle-like spines arranged near the base of the leaf stem. These can easily penetrate skin and even protective clothing.

 

To care  for your dwarf date  palm, keep the root ball evenly moist, allowing the plant to dry out only in winter between waterings. Mist frequently, and feed weekly (except in winter, when a bi-weekly feeding is optimal) for best results.

 

8. Ficus Alii (Ficus macleilandii “Alii”)

The Ficus Alii is effective at removing chemical vapors from the air and grows easily indoors, resisting most insects. It prefers a humid environment and full or semi-sunlight, though it will tolerate lower light conditions. Its ideal temperature range  is between 65 F and 85 F (16-24 C).

 

The Ficus Aliii should not be placed near heating or air conditioning vents, or near drafts because this could cause leaf loss. Soil should be kept moist but allowed  to dry out between watering. If your plant’s leaves turn yellow, this may indicate overwatering.

 

During the plant’s active  growing season (spring through fall), fertilize with diluted liquid fertilizer monthly (in a sunny location) or bi-monthly (in lower light). Ensure your fertilizer doesn’t contain boron, since the plant is sensitive to that element. Also be aware that the Ficus alii is poisonous and should be kept away from pets and young children.

 

In its tropical  habitat, Ficus alii will grow into a large evergreen tree. When grown inside as a potted plant, however, the Ficus alii will reach approximately 10 feet in height.

 

9. Boston Fern (Nephrolepis exaltata “Bostoniensis”)

In the studies conducted by Dr. Wolverton, the Boston fern ranked  the highest out of all plants tested in its ability to remove formaldehyde from the air. Since formaldehyde appears in everything from plastic garbage bags to paper towels, facial tissues, floor coverings, and adhesives—and gas stoves and tobacco smoking also release this chemical—the Boston fern is a smart addition to any household or office.

 

The Boston fern grows to four feet in height  with a spread up to five feet. It has feathery ferns, which are best displayed as a hanging plant or in a pot placed on a pedestal. It prefers a cool environment, bright but indirect  sunlight, and regular  attention. Keep the soil barely moist and mist frequently with warm water  or the plant’s leaves will turn brown.

This plant is prone  to spider mites and whitefly, which can be controlled using a soapy water  spray. Aphids may also attack Boston ferns if nearby.  Inspect new plants for bugs before bringing them home.

 

When the plant is producing new foliage, feed weekly with diluted liquid fertilizer. During the winter, feed sparingly. Never let the root ball of a Boston fern dry out. A humus rich potting soil will support the plant’s needs and help ensure you don’t need  to water  daily.

 

Boston ferns prefer to be somewhat potbound, so only move to a bigger container when roots

 

begin peeking through the drainage holes or if water  runs directly through the pot. Repotting is best done  in the spring, when the plant begins actively growing again.  The ideal temperature range  for a Boston fern is 65-75 F (18-24 C), dropping down to 50-65 F (10-18 C) at night.

 

10. Peace Lily (Spathiphyllum "Mauna Loa")

Excellent for removing alcohols, acetone, trichloroethylene, benzene, and formaldehyde, the Peace Lily also has a high transpiration rate to both purify and humidify indoor air. Its ribbed, glossy green leaves grow on stiff stalks that produce the characteristic white ‘flower,’ making  it one of the few tropical  plants that blooms indoors.

 

This hardy plant also tolerates neglect. Its ideal situation includes indirect  sunlight and high humidity, but it will grow in semi-sunlight or semi-shade when placed out of drafts. For best results, the Peace Lily should be thoroughly watered, then allowed  to go moderately dry between waterings. The leaves should be misted frequently with warm water  and washed occasionally to prevent

attack from pests like scale insects and spider mites.

 

Toxic to humans and pets, the plant’s leaves contain calcium oxalate and should be kept away from children.  The compact plant grows to a height  of three  feet with a two-foot spread, preferring temperatures between 60-75 F (16-24 C) during the day, with slightly cooler  temperatures at night.

 

Blog post submitted by Paula Fields  12-14-2018

My Favorite Realty Inc.   336-543-8683    PFields2@triad.rr.com