Have sympathy for those unfortunate enough to wake one morning to find their Tibetan cherry tree uprooted or their favourite gnome swiped. Hali-fax Home Insurance says that the average value of a claim for garden theft has risen by more than 25% in the past five years; Direct Line estimates the one in five of those with gardens has had something stolen from it.

Much of the theft is organised and specific. Tools and metal furniture are popular targets, but plants are often stolen, too: some people awake to find that their newly laid lawns and specific trees have been removed, while the rest of a garden is left intact. Other thieves have more idiosyncratic tastes: last year, Karen Stenhouse, a mother of three from Clackmannanshire, in Scotland, was convicted of swiping £700 worth of gnomes.

One solution is insurance: a report published this month in Which? Gardening cites Admiral, Budget and the Post Office as offering the best combined home/garden cover – although these don’t protect plants – while Insure4Retirement, Saga and RIAS offer the best policies for topping up existing home cover.

Better still, try to prevent thefts in the first place. Here are some tips: Light and sound: If you invest in only one thing to prevent garden crime, make it lighting – but the right type. PC Ian White, crime-risk manager at West Mercia Constabulary, suggests dusk-to-dawn photoelectric cell lighting rather than passive infrared, which comes on via sensors. “Continuous low light puts criminals off because they have to pass through it and risk being seen,” he says. Make sure it is not so bright it irritates the neighbours: they may not feel so inclined to let you know when they hear someone clamber over your fence.

Sound is also a good deterrent. If you don’t have a guard dog – or it is not up to the job – try a gravel driveway or paths so you can hear people coming. Sheds: As people have been spending more on garden equipment, so more of it has been stolen from their sheds. In mid-Sussex, for example, total crime fell by 15% between mid2006 and mid2008, but the number of thefts from sheds rose sharply. Local police have responded by distributing tamper-proof acrylic labels free to residents, which can be attached to lawnmowers or other tools. “Once stuck on, they’re impossible to unpick, and thieves find it harder to sell labelled goods,” says Inspector Marcus Potter, of Sussex Police, who devised Operation Green Stripe. The area now has only one or two shed thefts a month. Other forces are expected to follow suit soon.

Potter also recommends fixing tools to the floor with a chain and placing a bar across the door rather than using padlocks, which are easy to wrench off. Bars are available for about £50 from Gardien (www.garden-security.co.uk). Hot metals:There has been an increase in the theft of metal from gardens, especially gates and furniture, in part because of recent rises in the price of scrap. Despite the economic downturn, which is sending prices back down, this is likely to remain a problem. White suggests fitting gates with hinge pins, so they can’t be lifted off, and fastening furniture to the ground. “Anything that increases the time it takes to steal the object will put thieves off,” he says. Avoid temptation: It isn’t just tools and furniture that go missing; green-fingered criminals also take plants.

Front gardens are the easiest targets; hanging baskets and pots are the first to go, but occasionally plants and bushes, or even trees, are dug up.

Police recommend bolting down pots and putting a brick in the bottom of them, which makes them heavy to carry, but it’s also worth hiding expensive or exotic specimens in your back garden. Thieves are less likely to steal a buddleia tree, say, than an expensive Japanese maple or fancy topiary. A “rootball anchor”, which secures small trees to the ground, is available from Gardien for about £60. Prickly plants: Hedges of thorny plants such as ber-beris or holly make good barriers; plant them under windows to protect your home as well. Or thread prickly plants such as rambling or wild roses and blackberry through hedges and trellises. They’re more attractive than razor wire or broken glass, but just as effective, and without any legal complications. A boundary line of yuccas will make a front garden attractive and painful to enter by routes other than intended. Dark areas of a back garden can be made impassable with mahonia, a sharp evergreen shade-lover that has fragrant flowers in winter.

For more suggestions, visit www.met.police.uk/crimeprevention/garden.htm

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