I saw a Chilean red wine advertised as ‘dry-farmed.' What does that mean?

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Dry-farming or dryland farming means the crops aren’t irrigated. Natural rainfall provides the necessary moisture to promote the growth of the vine and ripen the grapes.

This practice isn’t worthy of a sales pitch in many established wine regions, particularly in Europe. It is how vineyards have always been cultivated in Burgundy, Bordeaux and other venerated wine growing spots. The only allowances for irrigation in areas of France, Italy, Germany and Spain would be to establish young vines or extreme drought conditions where the health of the vine is threatened.

But for regions where irrigation is common, dry farming is a point of difference.

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Advocates, such as Frog’s Leap in Napa Valley and Moss Wood in Western Australia, maintain turning off the tap yields higher-quality grapes with more fruit and aromatic intensity. Dry-farmed grapes typically have smaller berry sizes compared to ones that have been irrigated, which means more concentration and character for the resulting wine.

Members of Oregon’s Deep Roots Coalition, which include top producers like Evening Land, Eyrie Vineyards and Trisaetum, believe irrigation prevents wineries from capturing the true essence of their vineyards.

One of the major benefits of irrigation is the ability for grape growers to increase yields. Many of the value-priced wines from Australia, Argentina, Chile, California and South Africa couldn’t exist without this volume of fruit.

But technological advances and research means it’s not as simple an equation as decreasing quality to increase quantity. A considerable amount of highly collected, top-scoring wines come from irrigated vineyards.

Some wine regions wouldn’t exist without irrigation. Grape vines need water. Vineyards surrounded by trees or featuring other crops need to compete for water, while some grape varieties are more dependent on water than others. The water holding capacity of the soils is also a significant consideration about whether the yearly average rainfall is enough to sustain vineyards.

Dry-farming practices have become more common as climate change and the need for water conservation force the hands of wine growers to become more sustainable, especially in arid areas prone to drought conditions. Some producers now use their irrigation systems only in extreme circumstances.

Montes Winery in Chile’s Colchagua Valley began to embrace dry farming in 2009. Irrigated vines have shallow roots as they have never needed to develop root systems in search of moisture below the top layers of soil, so it’s a risky venture.

By 2012, Montes curtailed irrigation across 300 hectares, including vineyards responsible for its flagship M, Folly and Purple Angel labels. The driplines are still in place, should the vines need a drink.

Owner Aurelio Montes reports the vines produce half of the crop compared to the expected yields when they were bulked up with additional water reserves. Irrigation continues for the vineyards that provide the fruit for Montes’ more affordable wines.

Further south, in Maule, Chile’s oldest wine-growing region, a large number of family owned vineyards never introduced irrigation and have unwittingly found themselves ahead of the trend. The local Vigno movement, an association of producers looking to market the robust red wines made from old Carignan vines, broadcasts dry-farmed on all of its labels.

Most producers don’t make a virtue of where the water for their vines comes from, so seeing “dry-farmed” on a label can easily cause confusion. It is certainly a factor to consider as you look at a range of wines available, but the suggestion that use of irrigation or not is useful in determining a wine’s quality doesn’t hold water.

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