Interior decorators know that a potted plant can add life to a room, but these leafy greens are more than just pretty accent pieces - they can even make you healthier.

We dug through decades of research to find the feel-good effects of mixing a few houseplants into your home decor, from boosting your creativity to beating the sniffles.

Experts say you should amass as much green as possible. Your body will thank you and so will your wallet - have you ever compared the cost of a fern with the price of a Picasso?

Read on to find the best plants for every room - and exactly what to do to reap the health benefits. Blooms away.

To de-stress

Put a dragon tree in the room with the smallest windows.

A little green can instantly chill you out, finds a recent survey from Sweden. City dwellers there who frequently visited areas with grass and trees reported fewer feelings of burnout and panic than those who rarely saw greenery.

It's not entirely clear why, but many studies have found something similar, says Virginia I. Lohr, PhD, a professor at Washington State University who has been studying the subject for more than 30 years.

It's suggested that evolution wired humans to know that plants are essential to survival, so seeing one makes us calm and settled.

In one of Lohr's studies, people who worked in a windowless computer lab that had common houseplants such as bamboo palm, Chinese evergreen, snake plant, or arrowhead vine - all can grow well in low-light settings - had a four-point drop in their systolic blood pressure after taking a stressful computer-based test, compared with only a two-point drop in a group that had no exposure to plants.

That extra two points is equivalent to taking about half a blood-pressure pill, and "every point counts," says Douglas Reifler, MD, a professor of general internal medicine at Northwestern University.

To spark creativity

Decorate your office with small but colourful African violets.

In a study from Texas A&M University, women who worked for an hour in a room decorated with two potted plants and a bouquet of flowers generated 13 per cent more ideas than women in a room with abstract sculptures.

Studies show that plants are a mood booster, and good moods are associated with higher levels of dopamine, the hormone that controls the flow of information throughout the brain.

Your next bright idea: Head to a nursery or garden store and pick up a few houseplants of your own.

To fight colds

Place an ultra-leafy plant, such as a philodendron, in your bedroom.

Dry air can lead to a parched nose and throat - and raise the risk of infection or run-of-the-mill sinusitis, says Michael Janson, MD, author of User's Guide to Heart-Healthy Supplements.

But houseplants can inject moisture back into the air and boost humidity by up to 5 per cent, finds research from Bavarian State Institute of Viticulture and Horticulture in Germany.

A humidifier would do more, but the natural boost from plants is enough to help alleviate symptoms.

According to a study from the Agricultural University of Norway, people with table and floor-standing plants in their offices reported 37 per cent less coughing and 25 per cent less hoarseness after three months than when they left their offices plant free.

The researchers used heart-leaf philodendron among other plants, but you can choose the greens that are most appealing to you.

Just pick a plant that has a lot of leaves, because these types release the most moisture, says Sarada Krishnan, director of horticulture at the Denver Botanic Gardens.

To fight dry air while you sleep, try any indoor ivy variety, such as English ivy, or peace lilies and African violets.

The more plants you have, the greater the benefit. Grab a few large pots and plant several smaller varieties into each.

To cut exposure to harmful chemicals

All plants filter toxins from the air - so pick your favourite and put it next to your printer.

If you use a lot of cleaning supplies, or if you have a printer or newly painted walls or varnished furniture, you have VOCs (volatile organic compounds) - toxins that can cause dizziness, fatigue, nausea, kidney or liver damage, and even cancer.

A recent study from the University of Technology in Sydney, Australia, looked at the ability of two widely available houseplants - the Janet Craig, a standing plant, and the Sweet Chico, a smaller table plant - to strip VOCs from the air.

Researchers found that five Sweet Chicos and one Janet Craig may reduce VOCs in a 130-square-foot room such as a guest bedroom by up to 70 per cent.

When plants take in oxygen and carbon dioxide, they also pull in any toxins floating around in the air, says Kyle Wallick, a botanist at the United States Botanic Garden in Washington, DC.

The toxins travel through the plant, ending up near the roots. There, bacteria in the soil break down the chemicals into nontoxic compounds that the plant uses for food.

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