In 2004 the Make Space for Nature campaign encouraged people to make their gardens wildlife-friendly.

The Bugs survey (Biodiversity in Urban Gardens) in Sheffield has attempted to analyse what impact the campaign has had on nature, the BBC reports.

"All gardens have some kind of biodiversity value," professor Kevin Gaston, who led the project, told the broadcaster.

"Not in terms of every garden has something rare or stunningly important, but it's possible for all of them to contribute to populations and to ecosystem processes."

Gardens have been found to make a significant difference to some bird species. For instance about a third of the breeding blackbird population is in urban gardens, as well as 38 per cent of greenfinch and 62 per cent of house sparrows.

"There are some species, things like starling, that really do seem to favour small urban gardens that have a large area of lawn," Mike Toms from the British Trust for Ornithology explained.

Last month the RSPB requested gardeners to let their hedges and bushes grow slightly wild this year in a bid to help nesting birds.

For advice on caring for your lawn, visit Lawns.