Claret with horse power: How one top French vineyard went 'green'

The vineyard favours animals in place of tractors, and nature instead of chemicals.

Just north of the small town of Pauillac on the banks of the Gironde estuary, the great Bordeaux châteaux bunch like grapes on the vine. Mouton Rothschild; Lafite Rothschild; D'Armailhac; Pontet Canet. All have been been celebrated for their rich, dark wine for two centuries or more.

The vineyards sprawl over gentle slopes of gravel, sand and pebbles, less than a kilometre from the river. On this chilly spring morning, with the first leaves of the 2010 vintage showing on the vines, the vineyard workers are busy turning the ground between the rows.

For the most part, each château is surrounded by its own domain. In other places, the rows of vines are jumbled like a patchwork quilt, with the plots separated by, at most, paths or narrow tracks. You might find 12 rows belonging to Lafite; followed by 12 rows of Mouton and 20 rows of Pontet-Canet. The workers know precisely which vines are which. Less so, the perplexed visitor.

This spring, however, there is an easy way to tell the vines apart. In many places, the thin soil is being ploughed by noisy tractors with wheels on long stalks. In other places, the rows are being turned by elaborate, colourful carts, fitted with lights and solar panels and pulled by horses.

Horses? Can this be a tourist stunt? Horses disappeared from French vineyards more than half a century ago. But there are no tourists in the Haut Médoc vineyards at this time of year, only hundreds of wine critics and traders who have flown in from all over the world to taste the – reputedly sublime – primeur, or young, 2009 Bordeaux. Such visitors take no interest in picturesque horses working in the vineyards.

Maybe they should. The horses are part of an experiment by Pontet Canet, the only top château in Bordeaux to have gone entirely green, or "bio". The château uses no artificial fertilisers or pesticides, believing that the pebbly terrain of this part of the Haut Médoc has "magical properties" that should be respected. In other words, the gravelly soils and sub-soils, with their natural nutrients, minerals and micro-organisms, produce better wine if left unsoaked in chemicals.

It may, or may not, be a coincidence that "green" Pontet Canet, a château theoretically from the lower second division of the Bordeaux hierarchy, has risen in recent years into the wine aristocracy (in all but its relatively restrained prices).

The horse trial is the latest stage in Pontet Canet's drive to improve its already superlative quality. But how can using horses improve the taste of a wine? Alfred Tesseron, 62, the proprietor and president of Pontet Canet, is a passionate, friendly man who is devoted to the quality of his wines but is not afraid to defy conventional wisdom and take risks. "Year after year, vineyard machinery has been growing more elaborate, more expensive and more comfortable for the people who use it," he says. "The tractors now have stereos, air-conditioning. The machinery is much heavier. An impacted soil is a less natural soil. A less natural soil produces less healthy plants. Less healthy plants produce poorer grapes. We have decided to experiment by bringing back horses." Pontet Canet has three horses so far, of the medium-sized, pale chestnut (with white socks) Breton breed. This year, the mares Opale and Reine and the gelding Kakou will plough, spray and cart the grapes from 24 hectares (about 60 acres) of vines. Next year, Mr Tesseron plans to increase his herd to 10. He plans to sell his remaining tractors and turn over all 81 hectares (200 acres) of Pontet Canet to horse power.

The man behind this back-to-the-future experiment is Pontet Canet's manager, Jean-Michel Comme. "We have taken a decision to trust the soil," he says, as we admire Reine ploughing between the vines. "It's a lovely sight and a great pleasure, and much quieter, to work with horses. But we are not doing it for poetic reasons. We are doing it for practical reasons. Over the last 20 years, we have been building up the quality of Pontet Canet, brick by brick. We have improved the quality of the vines; reduced our yields; improved the quality of our wine-making equipment and methods. The next brick in the wall was to go bio. The final brick is to use horses."

Back at the château, he proudly shows off his horse-drawn machine for ploughing; another colourful machine for spraying (with nettle-based and other organic sprays); and a machine for digging holes for new vines. All have lights and solar panels to recharge their batteries. All have comfortable seats so that the vineyard workers do not have to walk behind the horses all day. "Machines did not exist for horse-operated work in vineyards," says Mr Comme. "So I invented them. I imagined them as I lay in bed at night. And we built them ourselves."

Some other French vineyards have, like Pontet Canet, gone over to "bio" or "green" methods. No other great Bordeaux vineyard has gone 100 per cent bio. No other top vineyard in France uses horses. Most of the famed Bordeaux châteaux – like Mouton and Lafite, whose recent vintages sell for €400-€500 (£350-£440) a bottle, compared to €50-€90 for Pontet Canet – still use chemical fertilisers, pesticides and fungicides.

Arguably, this addiction to chemicals is a nonsense: a denial of what we are told defines the best wines, French or otherwise. To boast their philosophical difference from New World wines, the French have invented or rediscovered a wonderful word in the last two decades – terroir. Terroir means, roughly speaking, soil conditions, plus lie of the land, plus micro-climate: all the factors which decide why a certain patch of ground produces good wine rather than bad wine; or great wine rather than good wine.

The individual wine grower, according to French purists, is a custodian of the terroir and its traditions: he does not so much "make" the wine as encourage it to achieve the full potential of its terroir, its typicité – meaning all the characteristics of bouquet, colour, taste and longevity that differentiate one wine from another one produced with exactly the same kind of grapes a few miles away, or even a few metres away.

If soil is so important, why do some of the custodians of the best terroir soak their land in chemicals? Jean-Michel Comme, Pontet Canet's manager, shrugs. "It is very complicated. If you are the owner, or manager, of a great vineyard, it is difficult to take risks which you think might lose your whole annual crop – or the vineyard itself.

"So you carry on using pesticides and fungicides and artificial fertilisers because that is what you have always done. It was perhaps easier for Mr Tesseron, as proprietor and director, to take such risks than for someone employed by absentee proprietors." Risks? "Yes. We are passionate about what we are doing but we know that we are risking our livelihoods and our lives.

"In 2007, we had an attack of mildew at Pontet Canet which threatened the whole harvest. In the end we lost 20 per cent of the crop – which was bad enough. Since it was me who had persuaded Mr Tesseron to abandon the use of protective chemicals, I felt terribly guilty I could not sleep at night. I was suicidal. That is why I say we are risking our lives, not just our livelihoods." Mr Tesseron decided at the height of the 2007 attack to suspend the "all-bio" method and revert, temporarily, to using a systemic chemical product against mildew.

He now says that he regrets this decision and would not repeat it: "I'm not sure the chemical product helped much, and we now know much more about how to use the proper doses of organic protection against mildew." Pontet Canet uses the same bright blue "Bordeaux mixture", based on copper, that is approved for organic use on tomatoes and potatoes in gardens.

Mr Tesseron, whose father bought the château in the late Seventies, says he been driven for 30 years by a simple calculation. Château Pontet Canet's vineyards adjoin those of the Mouton and Lafite. In places, as we have seen, the rows of vines are jumbled together. Should Pontet Canet not be able to grow wines to rival those of Mouton and Lafite? "We have been gradually building our quality in that direction. Now our aim is to be as natural as possible, in the belief that it is nature that gives a great wine its typicité. We no longer 'green harvest' (thin out the immature grapes). We no longer remove part of the leaves from the vines. By making Pontet Canet more natural, we believe that we will allow its true and special characteristics to be expressed more fully. We believe we will achieve the full value of the special terroir that we are so lucky to have. Our wines will not be just good, but still more recognisably different from all the others."

We tasted several vintages – 1990, 2001, even the infant 2009. All were extraordinary and extraordinarily different one from another. All had the depth – the sense of ridge after ridge of taste stretching away forever – that characterises a great wine.

Mr Tesseron insists, like Mr Comme, that Pontet Canet's pioneering approach to organic and horse-drawn production of great wine is rooted in pragmatism, not idealism. "If it doesn't work, we'll do something else," he said. "But it is my impression that it is working."

And not just his impression. Pontet Canet's tasting scores from celebrated wine critics, including the great American wine guru, Robert Parker, have soared in recent years. According to the 1855 classification of Médoc vineyards, Pontet Canet is a "cinquième cru" or fifth growth.

In other words, a great wine but not among the very greatest. Robert Parker wrote recently that Pontet Canet had skipped several levels and should now be considered a "super second growth... at half the price".