Humans evolved on and have walked the earth for tens of thousands of years and throughout this time plants have played a vital role in human lifestyle. The evolutionary links with plants are deeply rooted in our genes and even today this manifests itself in a variety of ways (for example, did you know that we can distinguish between two thousand shades of green but only a few of red). In the modern world we increasingly spend more time indoors either at the work place or at home. The internal environment can in itself produce harmful substances from a variety of sources and the airtight nature of modern homes traps these toxins inside the building.

Did you know that the indoor environment may be
5 to 7 times more polluted than the exterior?
(1994 CSIRO review)

Interior plants apart from looking good have been proven to have significant health and wellbeing benefits.

This is because of two major effects:

Physical - the cleaning, purification and conditioning of the air we breathe;

Psychological - the very presence of plants has been shown to increase positive feelings and reduce feelings of anxiety, anger and sadness.

There is a wealth of scientific study into the beneficial effects of plants in the interior environment including a large NASA programme.

If you are interested in more detail refer to

www.healthygreenatwork.org

(run by NIGZ, the Netherlands Institute for Health Promotion and Disease Prevention) for a comprehensive bibliography and further links.
The major health and wellbeing benefits of interior plants include:

• · Absorption of harmful substances
• · Filtration of dust and dirt from the environment
• · Dampening of sound levels
• · Reduction of stress levels
• · Increased humidity levels
• · Cooling effect
• · Lifting of the general mood
• · Emission of oxygen refreshing the air

These benefits are important in achieving a good and healthy indoor climate in the artificial environment of the workplace as well as the home.

These effects may be particularly helpful for respiratory and allergic conditions.

Recommended Top 10 Plants For Cleaner, Fresher Air

Here are 10 recommended interior plants rated for their ecological benefits (source: interpreted from NASA studies and NIGZ lists). These plants have been selected according to ease of growth and maintenance, resistance to pests, efficiency at removing chemical vapours, and transpiration rates.

Areca Palm (Chrysalidocarpus lutescens)

The areca palm is one of the most popular and graceful palms. It is tolerant of the indoor environment, releases copious amounts of moisture into the air, removes chemical toxins, and is also beautiful to look at. The areca is consistently rated among the best houseplants for removing all indoor air toxins tested. This plant can be kept best in semi-sun.

Lady Palm (Rhapis excelsa)

This large palm has fans 6 - 12 inch wide that consist of between four and ten thick, shiny leaves. Lady Palm is one of the easiest houseplants to care for and is highly resistant tot attack by most plant insects. It is also one of the best plants for improving indoor air quality. It grows slowly and is easy to maintain. This plant can be kept best in semi-sun.

Bamboo Palm (Chamaedorea erumpens)

Most members of the palm family are easy to care for and continue to be popular houseplants. In terms of its atmospheric benefits, the bamboo palm has an excellent overall rating and one of the highest transpiration ratings. It pumps much needed moisture into the indoor atmosphere, especially during winter months when heating systems dry the air. This palm is also one of the top-rated plants tested for the removal of benzene, trichloroethylene and formaldehyde. This plant can be kept best in semi-sun.

Rubber Plant (Ficus elastica)

Bred for toughness, it will survive in less light than most plant of its size. It will tolerate dim light and cool temperatures. This plant is easy to grow and is especially effective at removing formaldehyde. It receives high marks in all categories and is an excellent overall houseplant. Of the ficus plants tested to date, the rubber plant is the best for removing chemical toxins from the indoor environment. This plant can be kept best in semi-sun and semi-shade.

Dracaena fragrans"Janet Craig"

The dark-green leaves of dracaena "Janet Craig" make it a most attractive plant. It is one of the best plants for removing trichloreoethylene. These plants can tolerate neglect and dimly lit environments. This plant can be kept best in semi-shade and will tolerate dimly lit areas, but growth will be slow.

Philodendron

These large handsome climbers are very tolerant of shady conditions and can make a architectural statement in a dark situation. In a NASA study they were shown to be particularly effective in removing formaldehyde molecules as well as other toxins.

Miniature Date Palm (Phoenix roebelinii)

This palm usually reaches a maximum height of 5 to 6 ½ ft. However, it is a very slow grower. It is best seen when given adequate space and is impressive standing alone, especially when given spot lighting. Because its natural habitat is underneath the canopy of dense, tropical forests, it adapts quite well to the low light levels and controlled temperatures of homes and offices. When its environmental needs are met, the date palm can survive for decades. It is one of the best palms for removing indoor air pollutants and is especially effective for the removal of xylene. This plant can be kept best in semi-sun.

Ficus Alii

This is a new ornamental fig that is rapidly gaining in popularity. Its slender dark green leaves make it an extremely attractive plant. It is much less finicky than the Ficus Benjamina, and is appealing both to the interior plantscape industry and to the home market. Like all species of ficus, expect some leaf drop until the plant adjusts to its new location. A magnificent large plant, its ability to help purify the air, ease of growth and resistance to insects make it an excellent choice for the home or office. This plant can be kept best in full sun and semi-sun.

Boston Fern (Nephrolepsis exaltata)

Ferns are probably one of the oldest groups of plants. Many have been found as fossils dating back to prehistoric times. The Boston Fern's stiff fronds arch out, drooping downward as they age. It is grown strictly for its foliage for it does not produce flowers. It is best displayed in a hanging basked or sitting upon a pedestal. As an indoor plant, the Boston Fern requires a certain amount of attention. It must have frequent misting and watering or the leaves will quickly turn brown and begin to drop. Of the plants tested, it is the best for removing air pollutants, especially formaldehyde, and for adding humidity to the indoor environment. This plant can be kept best in semi-sun.

Peace Lily (Spathiphyllum)

An outstanding foliage plant that also produces beautiful white spathes, the peace lily should always be included when seeking a variety of indoor plants. This plant has a high transpiration rate and enjoys the large water reservoir that hydroculture offers. It possesses all the qualities to make it one of the best indoor plants. The Peace Lily excels in the removal of alcohols, acetone, trichloroethylene, benzene and formaldehyde. Its ability to remove air pollutants and its excellent performance in all categories make it a most valuable houseplant. This plant can be kept best in semi-sun to semi-shade.