The value of retail goods stolen rose 20 per cent to £4.88bn in the year to June, according to the Centre for Retail Research.
The UK had the highest amount in value of shoplifted goods in Europe and was third behind the US and Japan globally, data from 1,069 retailers suggested.
Checkpoint Systems, which commissioned the report, said there had been a rise in "middle-class" shoplifters. It said more people were now stealing goods simply to maintain their standard of living rather than to sell them on.
HTA security adviser B to B Links marketing manager Jeremy Davies said: "The increase has to be linked to the recession. People want to steal luxury goods. There are more thieves out there than ever before. There are new thieves who may not have thought about it before who have a reduced income but want nice things and in many cases wouldn't think they were stealing."
Davies, who is advising Armitages in Yorkshire, added: "The garden retail market is now selling more mixed goods such as gifts and clothing. The high street has protection like tagging, CCTV, security guards and procedures so people have moved to easier targets, such as garden centres, which have a lack of internal policies on how to use deterrents effectively.
"Garden centres are easy to steal from because of their shape and size. But they are understandably more focussed on selling than having a crime-reduction policy. They are naive to the harsh realities of crime and are seen as soft targets."
Davies said garden centres should change key codes monthly, audit tills, vet employees and conduct exit interviews with staff.
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