Thanks to science we now know that nature is basically a wonder drug. Spending time outside helps hospital patients recover faster, eases depression and anxiety, boosts the immune system, reduces blood pressure, and even increases happiness. The only trouble with trees is that it is impossible to prescribe in pill form.

But while you can't shrink a tree to the size of a prescription bottle, you can miniaturize nature in the form of potted plants. And for certain patients, British doctors feel that's a great place to start. Some are actually prescribing houseplants to those suffering from anxiety and depression to help lessen their symptoms.

Rx: Get a couple of houseplants and call me in the morning.

A family medicine practice in urban Manchester "is prescribing plants to help people with anxiety, depression and loneliness," explains Metro's Laura Abernethy (hat tip to Treehugger). "The idea is that patients get herbs, veg and pot plants [this has nothing to do with medical marijuana; she is referring to what we in the U.S. call potted plants] to care for and they then bring it back to the surgery to transfer it to the communal garden."

"The new scheme -- believed to be a first in the country -- gives patients a chance to join in with further gardening and social activities. It's based on the idea that spending time in green spaces can help to lift your mood," she continues.

Backed by the city's health commissioners, the idea is rooted in solid science. As human beings evolved for millions of years out of doors, it makes sense that our bodies and minds are optimized for natural environments. And that's just what study after study has found. Getting out in nature makes the human body work a bit better.

And thankfully for the time-crunched urbanite, you don't need to hike all day to see benefits. One experiment found that just looking at a green roof for 40 seconds noticeably boosted office workers' productivity. Another recent British study showed that people saw significant health benefits from just two hours a week outdoors. This evidence points to the fact that even just a few potted plants around your home or desk could have a real effect on your well-being.

There are also other reasons to think the particular arrangement of this scheme might be especially beneficial to patients' health. By tying the care of the plants into a community gardening project, the initiative is also helping bring people together and battle the modern scourge of loneliness, which research has shown can be just as bad for your health as smoking 15 cigarettes a day (yes, really).

Not such a crazy idea

If you still think this sounds like hippie dippie craziness, you should probably be aware that this one doctor's office isn't the only medical team experimenting with unconventional prescriptions. Other practices in Scotland and Canada have been sending patients out into nature and even to art museums to improve their well-being for a while now.

Even hard nosed, numbers-driven Amazon invested in a dome filled with 40,000 plants for its Seattle headquarters. The retail behemoth knows the science and believes that exposure to nature has a measurable impact on employees' mental and physical health, and therefore on their performance.