Theft of items such as statues, garden furniture and garden tools are most common, but theft of rare plants and shrubs are increasing. And don't forget that old favourite - theft from washing lines.
Research commissioned by Zurich Insurance from Gallup showed that 11 per cent of garden owners, more than 4 million people, have had garden equipment, ornaments or plants stolen from their gardens. One police force estimated that the cost of such theft in its area alone is pounds 4m a year.
Householders are making a real investment in their gardens - the Gallup research showed that consumers spent pounds 1.9bn on garden products in 1998 and this is expected to grow to more than pounds 2.5bn by 2003 - but many are unaware that their extra garden equipment and tools may not be covered by their standard household policy. Figures from CGU Direct show that average garden and outbuildings claims are between pounds 400 and pounds 500, and can be as high as pounds 7,000. The most commonly claimed items are lawnmowers, children's toys and power tools.
Most insurance policies do allow for cover of items outside the house but within the garden, but this is usually restricted to things such as garden tools and furniture and excludes plants. Also, most policies will impose a limit of around pounds 400 on the scope of the cover.
Taking a sample of the most popular insurers, Direct Line's garden cover limit is pounds 250; CGU Direct and Sainsbury's Bank limit claims to pounds 300; Woolwich, Royal & SunAlliance and Lloyds TSB limit claims to pounds 500; and Norwich Union has a pounds 1,000 limit. Liverpool Victoria has three levels of cover: nil, pounds 500 and pounds 1,000. All state a pounds 50 excess and none cover plants, trees and shrubs planted in the garden.
It is also worth checking on cover for items left in locked outhouses or garages. Here, for instance, Norwich Union's cover limit is pounds 2,500 and Woolwich's is pounds 1,500.
Gardeners who want higher limits and wider cover have recourse to few alternatives among mainstream insurers - Zurich Insurance is one notable example. Zurich Home Solutions contents policy offers pounds 500 garden cover including garden furniture, tools and potted plants with pounds 50 excess. However, its buildings cover includes a special garden cover extension which costs pounds 18 a year and provides pounds 1,000 cover for theft and damage. Unusually, it provides cover for storm and flood damage, as well as covering such things as the first pounds 50 of claims relating to loss or damage by birds, animals, frost, or flood to lawn and loss or damage resulting from the felling or lopping of trees by you or on your behalf.
Apart from this, two insurance intermediaries, Towry Law and RV Hillier, offer schemes for garden cover. Towry Law's Premier Executive Policy offers pounds 2,500 standard limit on garden cover. The policy, underwritten by Lloyd's, does provide for special items to be covered through policy endorsements for additional cost. Keen gardener Roger Hillier, of RV Hillier, set up his Homeplan for Gardeners policy in 1996 by negotiating an exclusive deal with the insurer NIG Skandia, whose basic scheme covers contents on a per bedroom basis up to pounds 35,000.
The basic policy offers cover for garden ornaments and furniture up to pounds 2,000 with a pounds 1,000 per single-item limit, and cover for trees, shrubs, plants and lawns up to pounds 2,000 with a pounds 1,000 single-item limit. The Deluxe version of Homeplan for Gardeners has increased limits of double the amounts of the basic policy. "Acts of God" such as flood or storm damage are not covered. The standard excess is pounds 50, but, as with most cover, taking a pounds 100 excess means premium reductions.
Many older and retired people are keen gardeners and in recognition of this, Age Concern offers its Home & Contents policy. Underwritten by CGU, the policy provides pounds 500 cover for items left in the open. According to David Hoyle, insurance manager at Age Concern Enterprises: "The policy is for people aged 55 and over of modest means. It was designed 15 years ago in response to demand when people found that their insurance did not cover their gardens."
As part of the gardening revival and a move towards "organic" methods of cultivating vegetables, there has been an increased interest in allotment gardening. Cover is also available here through membership of the National Society of Allotment and Leisure Gardeners, underwritten by Axa Insurance.
n Contacts: RV Hillier, 01443 205410; Towry Law, 01753 554400; Zurich, 0800 731 4327; National Society of Allotment and Leisure Gardeners, 01536 266576.
Tips from the Association of British Insurers (ABI) to beat garden thieves:
n Lock away expensive items such as lawnmowers when they're not in use.
n Make sure that sheds and garages have adequate security, and that door and window frames can not be forced.
n Prune trees and shrubs near sheds, greenhouses and garages to prevent thieves working undetected. Consider planting thief deterrent shrubs, such as those with prickly leaves and thorns close to vulnerable entry points.
n Postcode valuable items, such as cycles and lawnmowers.
n Keep the garden well lit. Consider installing security lighting.