Downy mildew and record heat worry Italian wine as harvest 2023 approaches

Downy mildew in the vineyard is a serious and serious problem in many parts of Italy, as WineNews has reported for some time now and as also reported by agricultural organizations such as Confagricoltura, with producers who, after the abundant spring rains that lasted until the end of June, had to forcibly delay treatments between the rows. And the prolonged, scorching heat of these days is also being felt among the vineyards, where it is hoped that the same rains that fell in the spring will help, after allowing the crops to accumulate important water resources and cope with these days of high climatic stress. A complex picture, then, that presents many risks. And although producers still trust in their own abilities and that of the vine, a resistant, resilient and surprising plant par excellence, the need to manage the vineyard and deal with an increasingly less predictable climate is emerging. As some of Federvini’s member wineries recount.
“Above-normal temperatures are a situation that has been going on for four years now”, said Piernicola Leone de Castris, ad Leone de Castris, symbolic winery of Puglia, where “Five Roses”, the first and most famous of Italian rosés, was born. “In 2021, we touched 45 degrees. This year, thanks to the rains, we are arriving with healthy plants and the rich foliage helps us to better manage the temperatures, in fact, we are being very careful to defoliate the plants so as not to burn the bunches. At the moment we are experiencing a delay in the ripening of the grapes, but with the warm weather expected in these weeks we expect to be able to catch up. For downy mildew”, Leone de Castris continues, “the inconveniences it is creating are tangible and worrying: in our case, in fact, we estimate a loss of between 10% and 20%. If we look, on the other hand, at the general situation in Northern Salento we have a more severe situation with peaks of losses that are around 70-80%”.
The issue of downy mildew also worries Alberto Tasca, CEO Tasca d’Almerita, one of Sicily’s wine references: “Downy mildew infects vines in the presence of continuous rains. In Sicily we do not see it often, precisely because of the scarcity of rainfall during the development of the vineyards: we can therefore consider 2023 an anomalous year because of the continuous rains in May, which caused the parasite to develop almost everywhere in the vineyards, causing in many cases significant production losses. On our estates, we also witnessed the appearance of the disease, and not in all vineyards were we able to contain the damage within an acceptable threshold. It is necessary to increase efforts toward research and scientific training of technicians to achieve increasingly sustainable agriculture. Unfortunately, even today, downy mildew cannot be fully controlled by biological defense strategies except with high amounts of treatments, and the only way for winemakers to save the crop is to resort to synthetic substances. These molecules, while having a low environmental impact, still require careful dosing and good technical preparation in order to minimize the effects on the environment. Another issue is that of the harvest: thanks to the late spring rains”, Tasca notes, “the soils still have good water reserves and the vines are still in the vegetative growth phase, so the heat does not have great negative effects on quality. Towards the end of July, when the grapes will start the ripening phase, high temperatures could accelerate the evolution with deleterious effects on the quality balance of the musts with low acidity, high alcohol content and poorly evolved tannins”.
From Sicily to Piedmont, from where comes the testimony of Chiara Soldati, of the renowned winery La Scolca: “the beginning of the season was rainy, with lower than normal temperatures, which made it possible to store good water resources compared to 2022. Despite the sudden rise in temperatures that lead us to expect a start of the harvest for the last week of August, the management of the leaf system and soil in recent months has been fundamental in order not to waste water resources and preserve the clusters. This allowed us to maintain ripeness in line with the company policy of producing wines with an alcohol content within 12 degrees. Finally, the abnormally hot weather presents us with an additional challenge: the consumer, with these high temperatures requires simpler products, which is why we have anticipated part of the harvest by offering a new product at 9.5 degrees”. Net of the harvest to come, however, downy mildew is also a concern in central Italy, where, explains Ilaria Palumbo, managing director Gotto D’Oro, “it is having a major impact on the vine. Daily rains for weeks, in fact, have prevented some producers from entering the vineyards and carrying out the necessary treatments, thus encouraging the proliferation of this vine disease. The high temperatures should slow down the ultimate pressure of the fungus, but the loss, to date estimated at 30% of grape production, still remains disarming. For the 2023 grape harvest, however”, Palumbo declares, “it appears extremely difficult to decipher for the moment, as we are still far from the presumed dates of the beginning of the harvest. What we can infer from the course of the last few months is highly variable, as so much has depended on the readiness of producers regarding the climatic adversities that occurred in May and June”.
“Our companies are deeply linked to the territories and the environment and we look with great attention to climate change”, says Micaela Pallini, president of Federvini, “and the phenomena linked to global warming are putting our territories and our companies to the test: if last year the problem was severe drought, this year the abundant rains have favored downy mildew. All of this teaches us to always be vigilant as we cannot predict the climate but surely arriving prepared will allow companies to face the challenges in the best possible way. In addition, it is essential to strengthen scientific research and obtain the support of institutions, which especially at the European level are often distant from our demands. For our part”, Pallini concluded, “the commitment of the supply chains we represent is to continue to be, more and better, decisive players in the protection of the environment, sustainability and culture of the territories. It remains crucial to obtain the support of institutions at the European and national levels for uniform and coordinated counter and preventive action during unpredictable weather situations. Wine is a fundamental asset of our culture and economy, which is why it is essential that institutions promote policies that can effectively support the growth of the sector”.