Therapy in green fingers

Those with green fingers have long known that gardening is good for you, physically and mentally. And now it has been proven scientifically.

Researchers have found that smelling roses and pulling up weeds can lower blood pressure, increase brain activity and produce a general upbeat feeling.

Even just looking at a garden can give you a positive boost.

The evidence is so compelling that the health factor has been given its own name - horticultural therapy - and is being used to treat hospital patients, plan cities and even to calm prisoners in jails.

Horticultural therapists say gardens produce the most positive effects on mental health.

They do this by providing a sense of control - the psychological counter to stress and anxiety. Gardens are also beneficial for stroke patients, those recovering from physical trauma or people with disabilities.

The science is now being used in hospitals and rehabilitation centres in the U.S., where 'healing gardens' have been created for patients to look at and walk through.

Doctors and nurses are also using the leafy retreats to cope with daily life-and-death crises.

'For patients who find themselves restricted by a disability, even the simplest gardening experience - such as growing a potted plant from a cutting - gives them a feeling of control,' said Teresia Hazen, who oversees horticultural therapy programmes in Oregon.

'Gardening, more than most rehab activities, has the ability to be very distracting. Simply by taking people's minds off their problems can alleviate pain and depression.' But the science is not just restricted to hospitals. Horticultural therapists are also being employed by major cities such as Chicago to help plan parks and botanical gardens.

Their patients are invited to join in the weeding, pruning, cultivating and harvesting.

Several schools of architecture now have academics on the staff to study what kinds of gardens are most likely to relate best to people.

Even New York's notorious Rikers Island Jail is using horticultural therapy to calm prisoners and prepare them for their release.

They take part in the prison's Greenhouse Project, which has transformed a neglected site into a small oasis with butterfly and bird gardens, a medieval-style herb garden and a waterfall.

Dr Roger Ulrich, a leading researcher on the effects of environment on behaviour from Texas A&M University, said: 'If researchers had proposed 20 years ago that gardens and gardening could improve medical outcomes they would have been met with derision and scepticism.

'We now have studies showing that psychological and environmental factors can affect psychological systems and health status.'

A number of experiments have led scientists to reach their conclusions. In one - reported in the Journal of Environment Psychology - researchers took 112 young, stressed-out adults and split them into two groups.

The first sat in a room with a view of trees and then strolled through a garden. The other sat in a windowless room and then walked in an urban environment.

The group that relaxed in the garden showed decreases in blood pressure and a positive change in feelings. Researcher Dr Terry Hartig, from the University of California in Irvine, said: 'Some of the changes could be measured within minutes.'