It's such a horrible event that the average wine region would go crazy if it rained just as they were about to celebrate veraison, right? If you are fussed by a few millimeters of rain per hour, the climatic conditions in Japan can be instantly fatal to you. We Japanese winemakers and grape growers can encounter precipitation of 100 mm per hour. For the past 10 years or so, the occurrence of rain clouds called linear precipitation zones has been realistically claiming human lives every year. Catastrophic rains, called guerrilla downpours, are frequent. Japan has a rainy season called the rainy season, but this year, the heat wave continued during the time when it usually rains, and a period called the "empty rainy season" lasted until three weeks ago. However, the rainy season has returned with the sudden occurrence of linear precipitation zones. The vines, which had been suffering from excessive drought, suddenly began to absorb water due to the sudden supply of rainwater. Downy mildew has been frequent in areas where canopy management has been neglected, and we have been busy with pesticide spraying operations. However, vineyards in Japan are fragmented and not consolidated, and in most cases, the size of a single field is not even 0.5 ha. This means that you need to manage fields here and there at the same time, and task management is complicated. There is not always one disease that occurs, and the pesticides selected may not be able to handle all the diseases that occur. The number of pesticide applications often exceeds 10 times per year, making the selection of optimal pesticides a very difficult problem for farmers. Multiple factors are taken into consideration when deciding which pesticide to use, including whether the pathogen is drug resistant or not, the efficacy of the pesticide, whether it is for prevention or cure, the limited number of times, the mechanism of action, cost, and the risk of chemical damage from mixed use. Under such troublesome, hot and humid conditions, growers are still standing in the fields and working silently today. They are masochists! you may think, but the fruits of their labor are certainly beginning to produce great tasting wines.
What you see in these Japanese vineyards at this time of year are several types of rain guards. I have managed to rehack one of them and save up to 1/20th of its normal cost. Even if I didn't have the money, I'd still want to protect my grape bunches from the rain!