I’ve just come back from a trip to Bordeaux to assess the 2018 vintage. One of the unusual things about this vintage was that the harvest window for the red grapes alone this year was one of the longest—from early September to late October. Since, ultimately, it is the pursuit of that somewhat subjective concept, “ripeness,” that sets the style of the vintage and the quality, I thought it might be interesting to consider the mechanisms behind ripeness and how they played out under some of 2018s extreme conditions and emerging dogmas.

Firstly, it is important to understand that 2018 Bordeaux was a long harvest because it could be long. There was little or no threat of autumn rain on the horizon to make growers’ minds up for them. Secondly, the red berries were very small and thick-skinned this year with a lot of tannins to ripen. It was the view of most of Bordeaux that the tannins, in particular, needed considerable hang-time in order to fully ripen. But, of course, no one component in grapes ripens in isolation. Achieving tannin ripeness has an impact on sugars, acids/pH and flavor compounds and often there is a trade-off. 

Skin tannin or phenolic ripening, as it is sometimes known, differs in means, rates and timings from formations of the sugars in the flesh. For a start, grape tannin ripening, unlike sugars, is not merely a matter of accumulation; it also involves the development or polymerization of tannins from smaller subunits such as catechins into larger, seemingly softer and less bitter compounds. 

Tannin synthesis and development happen mainly within a narrower temperature band and at a different pace to sugar accumulation. So, in an ideal grape-growing world, the weather throughout the growing season will be relatively dry with temperatures and sunlight exposure that are “moderate” enough to slow the sugar accumulation while allowing tannins to progress at steady pace.

The word “moderate” is not featured heavily in my Bordeaux 2018 report. It was not a moderate vintage. Putting the extremely rainy start to the growing season and episodes of hail aside, July, August and September were particularly hot. “From mid-July it became very dry and very hot,” Château Lafite’s technical director Eric Kohler commented. “This was the hottest summer since 2003.”

Aroma/flavor compounds are equally fiddly things to get right in the berry ripening process. Some compounds increase as the grape approaches desired sugar accumulation levels while others can degrade. At the extremes of ripeness aroma compounds can either be severely diminished and under-developed or overblown, simple and lacking finesse. If a winemaker harvests too early in an attempt to force an elegant, crisp, lighter bodied/lower alcohol style of wine, the flavor compounds may be green, lacking or both. If the winemaker harvests too late, aiming for a big, full-bodied, concentrated style that the vine/vintage/site combination doesn’t necessarily want to give, some of the finer flavors may have started to degrade, giving way to a relatively simple and sometimes jammy, prune-like and/or baked fruit characters, particularly if the grape has started to shrivel or “raisin” on the vine.

2018 was also very dry from mid-July onwards. A significant issue facing producers and potential quality was, come September, how little rain the vines had received. By now, the generous water reserves in the early part of the growing season were depleted from the freer draining gravel and sandy soil profiles. Younger vines really suffered. “This was the first time I have seen such dehydration for the young vines,” Château Margaux managing director Philippe Bascaules told me. “This happened in September. The young vines were disappointing for us.” If this is happening at Margaux, readers can just imagine how many other tight-lipped producers were experiencing similar vine hydric stress and berry dehydration problems.

“The berries had a lot of tannins,” commented Cheval Blanc’s technical director Pierre-Olivier Clouet. “It was a challenge to ripen all those tannins!” Cheval Blanc also had a particularly long harvest, being among the last to bring in the final parcels of Cabernet Franc on October 11. “We had to wait for each plot to get the right maturity,” added Clouet. “This gave us these wines with great drinkability—very silky and round.” 

“If you pick early, you can get precision and aromatic typicity of this region,” Aymeric de Gironde of Troplong Mondot told me. “We began picking on September 7 and 70% of the harvest was done in a week and a half.” This was a good week before most other right bank producers even considered harvesting Merlot. “This year was a question of choices. Not every year do you have the choice of what to do. This year we could make a choice based on our beliefs. I was looking for purity of aromatics. My fear was because the skins were quite thick. I think I could have waited until Christmas and they wouldn’t have moved.”

These examples of Cheval Blanc and Troplong Mondot demonstrate two very different routes to very different styles of wines.

Let’s face it, in all but the world’s very best vineyards and vintages the conditions are not going to be ideal for the desired levels of sugar, acid, tannin and flavor ripeness to occur simultaneously. To maximize opportunities for this, it is so important to marry the right grape variety to a supportive climate and a complementary site as well as the adaptable, proactive/reactive annual canopy management decisions and a balanced crop load for reliable ripening. All of these factors came into play given the extreme weather conditions in Bordeaux in 2018, resulting in varying degrees of success. This year, there are some incredible WOW wines, some big disappointments and a lot of mediocrity. As subscribers will see in my full Robert Parker Wine Advocate report—2018 Bordeaux En Primeur: Extreme Vintage (a comprehensive look at the growing season, styles and quality of 2018 with nearly 800 barrel sample reviews)—most winemakers were forced to make some quality trade-offs somewhere along the line. This is agriculture, after all. Far more often than not the results are less than perfect. Paradoxically, this is both the most disappointing and the most exciting aspect of great wine.