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Can winemakers navigate excessive salt in soils?

18 September 2023 By Sarah Neish

With winemaking branching out into more remote corners of the world, db talks to one Chilean producer about its love/hate relationship with salt in the Atacama Desert.

As winemakers push further into unknown territories in a bid to outrun the effects of climate change, they inevitably collide with new and unforeseen challenges.

In the sun-baked plains of the Atacama Desert, which straddles Chile and Argentina, the biggest hurdle is not the fact that it is one of the driest, hottest places on Earth, with temperatures regularly climbing to 44 degrees. Rather, it is the large quantity of salt found in its limestone soils.

This white, grainy substance has prompted Chilean winery Ventisquero to push its innovations to the limits in order to continue making its range of Tara wines produced using grapes from the Atacama.

Having first planted vineyards in the Atacama in 2007, it wasn’t long before the team noticed something was “drastically” wrong.

“In our second year after planting, all the vines died,” Alejandro Galaz, winemaker at Ventisquero, tells db.

“We discovered that the soil contained a huge amount of salt – about 10 times more than vines are able to endure.”

The viticultural team’s solution was to carry out “long irrigations” of 18-26 hours for a period of nine to 10 days at a time.

At first, this method succeeded in moving the salt to a less problematic position in between the rows of vines. However, it was neither a failsafe nor viable long-term solution with water being such a precious commodity in the region.

Fighting salt with water

Three years ago, Ventisquero began experimenting with a sprinkler system instead, which used one third of the water it had been employing for the long irrigations.

“Deserts are full of salt, and drip irrigation causes that salt to rise,” chief winemaker Felipe Tosso tells db. “We began using small sprinklers instead to help spread the water out, which means less salt rises to the top of soils. It has increased our yields by 20% – and we should see the results in our wines that are released in 2024/2025.”

With the time of those releases fast approaching, db caught up with Tosso’s winemaking colleague Alejandro Galaz to find out how the latest Tara vintages (2021 and 2022), produced in the Atacama’s Huasco Valley, are showing.

“The sprinkler system for sure has been working much better,” Galaz says. “And we have been able to plant new rootstock that is resistant to salt.”

Despite how it might sound, Ventisquero is not interested in waging war on salt, nor seeking to eradicate it from the terroir. Instead, its winemakers are attempting to befriend and embrace the substance for the saline influence it has on its wines.

“If we had wanted to achieve ‘no salt’ then we would have abandoned the project and the location just one year after planting,” Galaz says. “If we were to remove all trace of salt from the wines then they would taste like a Sauvignon Blanc or a Chardonnay from anywhere else in Chile. We would be removing the essence of the Atacama.”

In short, there would be little sense in navigating the considerable 800km journey between Santiago, where Ventisquero is headquartered, and the Atacama just to produce another expression of the same wine.

“You can imagine the logistics involved in that journey!” quips Galaz.

Putting ego aside

The first step to success was admitting that they would never fully conquer the challenge, and nor should they try to.

“Anyone in the wine business knows about winemakers and their egos,” says Galaz. “In the Atacama, and in our vineyards in Patagonia, it has been humbling. We have had to put our egos aside.”

Not only is the salt present inside the Atacama’s soils, it also blows in via a thick fog known as the Camanchaca from the Pacific Ocean just 15km away. The fog descends like clockwork twice a day (at 10am and 6pm), enveloping the vines in a dense cloak of mist.

“Local people used to collect drinking water from these fogs using nets made from seaweed,” recalls Galaz.

The humidity from the fog in fact brings welcome hydration for the vines: “It’s like a little miracle twice a day.”

In other words, there are fringe benefits to be found alongside the salt.

If further evidence were needed that Ventisquero is not in the business of battling salt, it can surely be found in its recommended food pairings for its Tara wines.

Rather than pairing Ventisquero’s Tara whites, which have a distinctive saline profile, with something contrastingly sweet, or even neutral to offer a tabula rasa for the wines to shine, Galaz suggests going for… more salt.

“I highly recommend oysters as a food pairing,” he says. Other suggestions for food matches are sea urchins and oily fish.

In a desert that is home to Chile’s largest salt flat, which spans 750,000 acres of the Atacama, it seems wise to work with its natural ingredients, rather than against them. And that is precisely what Ventisquero is doing.

This year, the producer releases its first single-varietal Grenache and Cabernet Franc wines from the Atacama as part of the Tara range, underlining its commitment to the challenging but rewarding terrain and to the continually evolving viticulture in this extreme region.