Aurelio Montes

The trial at his Argentine winery, called Kaiken, will start on Cabernet Sauvignon and Malbec as bud burst begins later this year, and follows a similar move to growing vines without water at the Montes property in Chile.

Montes admitted to the drinks business last month that he was “afraid” that the trial at his Mendoza vineyards “won’t work”, adding, “but if we fail, at least we will have tried”.

Growing grapes without irrigation is certainly a challenge: Montes plans to experiment dry farming at his 2 hectare Vistaflores property, where average annual rainfall totals no more than 330mm, and the soils are free-draining.

Situated at 1,250 metres above sea level, Montes said that the heat “was strong”, but believes that “the summer rain may help” with the trial, although the sandy soils may be unable to retain what little moisture there is for the vines, which were planted in 2011.

Montes began experimenting with growing grapes without water in Chile’s Colchagua Valley in 2010 and by 2012 moved to viticulture without irrigation across 300 hectares, encompassing all the red grapes for the Montes Alpha red wines, apart from Pinot Noir, as well as the producer’s “icon” wines, such as M, Folly and Purple Angel.

Explaining the motivation to begin the trail, Montes told db, “Five years ago, when I became sure that climate change was a reality and Chile was no exception, I thought it was irresponsible not to learn more about how to deal with drought, so I asked the viticulturist to stop irrigating a parcel of vines.”

Although the vineyard manager insisted that the dry farmed vines would die, Montes recalled, “What we learnt was that the vine adapts itself, so the first year it was on its knees, begging for water, but by the second year it had reacted, so the bud burst was later, the shoots and clusters were smaller, and the roots dug deeper.”

Nevertheless, the vines, which were 10 years old, didn’t produce any fruit in the first year without water, and today, the 300 hectares has seen its annual yield halve from 10-12 tonnes per hectare to 5-6 t/ha.

“It has been a big effort to preserve the price of the wine because the cost of the grapes has doubled,” said Montes, explaining that this was also the reason why he hasn’t extended the practice to the production of wines for his entry-level “classic series”.

On the other hand, Montes recorded that the water saved over the 300ha was enough to supply 20,000 people for one year – “or a small town” – although in terms of monetary value, this represents “only a small saving”.

Montes vineyards in Vistaflores, Argentina

However, it does mean that Montes has the water to plant a further 100 hectares in Colchagua.

“One of the big benefits is that I now have the water to plant more vines, but I’m not going to at the moment, because I want to see whether the climate goes deeper into drought.”

He also said that the vines without irrigation are producing better wines.

“A blind tasting with our six winemakers showed that wines made from grapes from full irrigated vineyards gained an average score of 88 points, while those from the non-irrigated vines gave an average of 92 points.”

In particular, the small clusters produce wines with greater phenol and colour concentrations, requiring changes to the winemaking for the Montes Alpha reds.

“The ratio of skin to pulp is 12% in irrigated vineyards, but grows to 37% in non-irrigated vineyards, so we have had to change the winemaking, so now we do very little pumping over, and we have reduced the temperature of fermentation from 30 degrees Celsius to 25, so we extract less [tannin],” according to Montes.

He also admitted that the “dry-farmed” vineyards do occasionally receive some water, as drip irrigation is already installed.

Although Colchagua’s annual average rainfall is around 500mm, the region receives only around 50mm in summer, which Montes said was sufficient. However, in those years where there is no summer precipitation, Montes said the producer would add 50mm to compensate.

Commercially, however, Montes said that he has yet to see the benefit from such a dramatic drop in water use at his Chilean operation.

“The effort has been huge, but how do we communicate that? It is difficult, and people don’t understand the concept of dry farming,” he said.

Nevertheless, concluding, he said, “It is a huge milestone, and when the drought comes, you will see most people crying, and I will be smiling.”