As a winemaker for 20 years in Chile, I was on my way last August to become the Director of Winemaking for Fall Creek Vineyards. The minute I got off the plane in Austin, I immediately thought Texas weather was just too hot for growing high quality wine grapes; it was something like 100ºF.
But, my scientific deformation prevented me from making a hasty decision, so I had to ask: is this a transitory heat wave? The answer was, “No, it has been, and it will be like this for several weeks.” Paradoxically, that answer seemed like iced water over the head. I knew I needed a couple more elements to prove my theory regarding the vines and the wines.
I expected to find shriveled berries, some raisins already and some sun-burned ones as well, so my eyes were with bias looking for these hot weather symptoms. Instead, the vines were just fine with good color, healthy canopies, and turgid berries that were ripping nicely. I was positively surprised.
Then, I found that the wines from previous vintages (even hotter than 2013!) didn’t show any sign of the effects of a hot year, like an unbalanced alcohol, less color on reds and jammy flavors, to name a few. That was when I really had no clue as to what was going on here. I mean, in cooler climates, where the average minimum and maximum temperatures fluctuate between, let’s say, 64 and 92ºF in the hottest month of the summer, a 1-to-3 days heat wave of, say, over 100ºF would affect plants so much that growers would face a significant loss of production like the one shown in the picture below (from Australia), and then the wines wouldn’t be the best of the decade, for sure.
So, there has got to be something special going on here that prevents plants from getting the effects of the Texas summer. And it seems that what happens is coming from the very inside of the plants themselves.
I asked Benjamin Lewin MW (former founder Editor of the life sciences journal, Cell) about the chance of some kind of adaptation of plants to heat, and he said that, in fact, that there is a set of genes, called heat shock genes, that are triggered precisely by exposure to heat. There it is, vines are loaded with an adaptation strategy to the hot summer kind of weather. And if we think about it further, this makes total sense if we consider that vines were originally cultivated and domesticated in an area between the Black Sea and Iran, where they experience even more torrid summers in some of these regions.
So, apparently, it is a good thing that our summer temperatures go up in a slow but steady way, so plants can prepare themselves for what is to come. Then, in the middle of the July-August period they are fitted with their own sun screen, allowing those wonderful grapes to ripen, so we can make world class wines. Stay tuned!
Fall Creek Vineyards
Director of Winemaking