For the winemaker, this means getting up early in the morning and occasionally at night to harvest into the rising sun. It is the oldest, when the sun is just before rising and around noon, the temperatures climb above 20 degrees celcius very fast. Many people are not even aware of the harvest going on, as there are only a few tractors and grape harvesters around during the day. However, due to the excellent health of the grapes, there is no need to rush the harvest.
The ideal harvesting temperature is 14 to 15 degrees Celsius, at which the grapes or must do not have need to be cooled, in order to cause a slow fermentation start. If the temperatures are higher, pre-clarification by sedimentation (allowing it to settle) is no longer possible and a great deal of energy has to be used just for cooling the must. Only for the red wine production, where slightly more heat does not do any damage, when the fermentation is done on the grape skins, a few degrees more can be tolerated fot a quick start of fermentation.
Due to the warm temperatures, it can already be said that the 2020 vintage will have a moderate acidity. The more it cools down at night, the better the development of the fruit aromas in the grapes will be. The yields vary gravely across Rheinhessen. Where there have been a few rain showers in the last few weeks, they are very good; where the soil has dried out like a desert, the vinegrowers harvest below-average quantities.