Gardeners are being urged to keep swapping and growing their favourite vegetables as old varieties of seed are under threat new EU regulations.

Heritage seed varieties are not allowed to be sold unless they have been given specific marketing consent and approved on an EU or UK list.

This has led to the disappearance of 98 per cent of vegetable varieties, according to Garden Organic, a conservation charity. Some 95 per cent of vegetables we eat today come from just 20 varieties.

One vulnerable variety is Colonel Murphy’s Dwarf French Bean. There is only one seed left in the Heritage Seed Library. The charity is now concerned that efforts to market vintage varieties will backfire and that many more favourite seeds will disappear. A new “conservation” varieties directive intended to encourage and promote these heritage seeds is due next year.

But people will have to pay at least £4,000 for the privilege, a high price for the seven million green-fingered enthusiasts as well as charities.

Bob Sherman, director of gardens and gardening at Gardening Organic, which runs the Heritage Seed Library, said: “It’s not just vegetable varieties we are losing but local history, culture, traditions and skills.”

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