No vintage is the same as the previous one. There are an infinite number of factors and conditions that have an impact on the quality and characteristics of the grapes we harvest each year. Luckily, our winemaker Ángel Anocíbar knows the area like the back of his hand, and although he cannot perform miracles, he uses some tools that enable him to be one-step ahead of problems. His first diagnosis for 2019 is pretty good.
At this stage in June, several parameters provide very precise information on the future 2019 vintage. Undoubtedly, the summer months are often critical and can make a difference for the better and, unfortunately, for the worse.
Temperatures. April was a cool month, which resulted in a rather irregular budding. So much so that the warm temperatures in May encouraged some plants to grow vigorously. However, the ones with delayed bud break were unable to benefit from this boost. “There were cold and heat strokes in June”, says Anocíbar. This is going to delay the vintage “a little”, although the current heat wave is helping “the vines to go strong” and make up for some of the time lost.
Water. It’s also an important fact. In contrast with the abundant rainfall in 2018, 2019 has so far been rather dry. While there have been years of greater drought, water reserves in the area are at 75%, suggesting that there will be fewer clusters and that these will be smaller. No bumper harvest is anticipated in 2019.
The heat index or GDD equation, a winemaker’s best friend
We have mentioned before that Ángel Anocíbar’s favourite tool to assess each harvest is the heat index or GDD (Growing Degree Days) equation. In short, it measures the temperature that the vine needs to complete its phenological state; that is, for the plant to grow and mature its fruit. It is calculated by adding the average daily temperatures that exceed 10º C from April 1 to October 25.
The graph below shows the preliminary GDD equation forecast for 2019 and the comparison with the cumulative data of Abadía Retuerta. This chart helps to identify at a glance the warmest and coldest harvests of recent times.
In the past and in some cold vintages, ripening is a great challenge in the Duero region, as it must occur in a shorter period of time than Rioja, for example. In this regard, climate change has had a positive effect in recent years. In the early nineties, the cumulative average temperature was around 1,200º C, but in recent years, it has risen to 1,400 or 1,450º C. “This has translated into an increase in plantings in cold areas like the moors, which are located at higher altitudes,” explains Ángel.
Another particularly valuable piece of information links the ODD equation with the growth of the vineyard in centimeters. It may sound a little bit technical -don’t worry, we are not going to talk about the equation that explains this link-, but this information is very useful for scheduling certain jobs in the vineyards such as green pruning, the raising of wires in the trellises to guide the vegetation, or pinching back shoot tips.
We have also asked Ángel Anocíbar to compare the 2019 harvest to previous vintages in the area. Which are the most similar to date?
“Right now it shares similar traits with 2010,” he notes. “It was a late vintage but it finally picked up a little, although harvest came a little later than usual”.
He also sees some interesting similarities with previous vintages ending in “nine”. According to Anocíbar, “both 1999 and 2009 were good vintages, not excessively warm and with no rainfall in the harvest, which made it possible to harvest the grapes without a problem. The pattern,” he points out,” involves late-ripening vintages that were harvested between mid and late October”.