Garden-grabbing is an emotive term used by campaigners who oppose the building of blocks of flats on land that was formerly private gardens. Neighbours who have had their view spoilt by these flats object to the Government’s definition of gardens as brownfield land, which leaves them vulnerable to property developers.

That view has to be balanced against the fact of Britain’s housing shortage: the Government’s target is 200,000 new homes each year, yet only 160,000 were completed in 2006. That lack of supply artificially inflates house prices and wrenches the first rung of the property ladder away from the reach of the majority of young people.

The issue hit the headlines last week, when the Conservative MP Greg Clark introduced a Private Member’s Bill calling for the removal of gardens from the definition of brownfield sites. He quoted figures suggesting that one in three new homes in the South East was now being built on former gardens, and that green space equal to 2,755 Wembley football pitches would be destroyed by 2016 if gardens were not protected. Mr Clark also argued last week that new homes built on gardens “are doing nothing to provide . . . affordable housing and homes for young people. Garden-grabbing developments typically replace family homes with high-priced apartments.”

The Royal Horticultural Society is one of the many groups concerned with the environment that are supporting Mr Clark’s Bill. Inga Grimsey, director-general of the society, is unhappy about the loss of “private green spaces”. The public, she says, should “demand better garden planning by developers”.

Development companies are now taking aim at those who see dollar signs in their garden. One such, Favoured Locations (www.favouredlocations.co.uk ), appeals to homeowners on its website: “You know of endless TV programmes about how to boost the value of your home. Now it is time to take your share of the property pie.” The company’s owner, Angus Bearn, says: “There is a great awareness now that there is money in property. People who get in touch with me are often getting divorced and selling up and want to make as much money as they can out of their land, or their mother has died and they want to maximise the value of her house before they sell it by building more homes in the garden.”

Portions of gardens are also being sold off by homeowners who prefer cash to mowing lawns. One couple, Zoë and Norman Carter, bought a plot of land that was originally part of someone else’s back garden in the north Cornwall village of St Breward, and have just built a new home on it. The neighbours objected. “Obviously people don’t like change,” says Norman Carter. “But we tried to combat this by using local builders and suppliers, which helped with some of the resistance.” Most of his neighbours have now come round, though he admits that a couple are still unhappy.

James Greenwood, of Stacks, the buying agents who acted for the Carters, says that garden-grabbing is on the increase: “Traditionally, it was associated with the South East but now it is a widening phenomenon. Rock in Cornwall is a prime example. There is huge demand for property here and developers are buying up any small piece of land they can lay their hands on. But a warning to potential developers: you will not be popular with the locals. Villagers will never be happy about more properties being crammed into their area.”

Those tempted to defy the neighbours and sell off the bottom of their garden should act soon: Mr Clark’s Bill is due to be heard in Parliament on October 19.

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