Food and Drink: Such a tasty Bishop's Choirboy: A potato library may hold the key to preserving our vegetable heritage, says Chris Arnot

Bishop's Choirboy sounds like one of those powerful beers found in real ale pubs. But it is a potato - one of hundreds of unusual varieties kept alive, just, by the enthusiasm of a few isolated growers.

Despite the boom in sales of pasta as a source of dietary carbohydrate, the British remain keen on the humble spud. It is still our most popular vegetable. Every year we consume more than 200lb per head of population. But of the 6 million tonnes grown annually by our farmers, two-thirds of the earlies and half the main crops are accounted for by just three varieties.

Now some of the supermarket chains are beginning to counter the trend towards standardisation. Such long-forgotten names as Pink Fir Apple and Dunbar Standard are appearing on the shelves - at a price.

Growing your own is a more economical way of sampling the wide range and subtle flavours of our potato heritage. Seeds for unusual varieties have been available from only three suppliers, and one of those, Websters of Arbroath on Tayside, recently went out of business. That leaves Edwin Tucker & Sons of Newton Abbott, and Margaret MacLean of Dornock Farm in Crieff, Perthshire, who has managed to keep 150 varieties going since the death of her husband, Donald, five years ago.

Scotland's cold and windy climate is inhospitable to the pests that wreak havoc on potato crops elsewhere in the British Isles, and the Scottish Office keeps more than 800 different types for scientific research.

In Warwickshire, the Henry Doubleday Research Association wants to make a much wider range of seeds available to the public through a 'potato library'. Subscribers will have access to about 280 varieties. 'We've had a seed library for some time,' says Jackie Gear, joint executive director with her husband, Alan. 'Now we want to concentrate on the potato. Sales have kept up only because of products such as chips and crisps. We want to push it as a quality vegetable in its own right.'

To raise consciousness and money towards the pounds 50,000 cost, the association is planning a Potato Day next Saturday at its headquarters at the Ryton Organic Gardens, near Coventry. There will be 35 varieties on show, including Bishop's Choirboy, grown in Suffolk since the early Forties, and Mr Govett's Belgian, brought to England by a soldier who married a Belgian after the First World War.

Visitors will be able to sample potato soups, potato bread and potato pastry at the centre's restaurant; Lynda Brown, former presenter of Gardeners' World, will host Potato Question Time, and there will be illustrated talks by Alan Wilson, author of The Story of the Potato, and by Jeremy Cherfas, head of genetic research at Ryton. He will discuss the micropropagation of seeds in laboratory conditions. Potatoes are notoriously prone to disease, and this is the most efficient way of keeping alive many strains threatened with extinction.

Membership of the library would cost pounds 12 a year. Those who joined would be able to choose six varieties annually. 'We'll send them little pots of mini-tubers, about the size of a marble,' Alan Gear says. 'That should be enough to get the seeds started.'

It should also avoid the restrictions of the European Community's 1973 ruling that only vegetable seeds which have undergone tests for 'distinctiveness, uniformity and stability' may be sold to the public. 'It cost up to pounds 1,000 to get on to the approved list,' Mr Gear says. 'We lost about 2,000 varieties of vegetable between 1973 and 1980, many potatoes among them.'

Market forces also took their toll on those spuds with an appearance that did not fit supermarket requirements. It was assumed there would be consumer resistance to varieties that looked knobbly or had a dark tinge to the skin. So much for Shetland Black, Edzell Blue and Purple Congo.

Farmers and large-scale growers went for high-yield varieties, irrespective of flavour. 'Some taste like packaged water,' Mr Gear says. 'The public has been short-changed by the race to produce high yields. There is less water per given weight in an organically grown potato.'

He believes the Ryton potato library will help to provide a much wider range of flavours, as well as preserving part of our horticultural heritage: 'If the two remaining specialist growers went bust, you would have 200 or 300 years of cultivation down the river.'

Potato Day, 26 February, 10am, admission pounds 2.50. Details: Jackie Gear, Ryton Organic Gardens, Ryton-on- Dunsmore, Coventry (0203 303517).

(Photograph omitted)