The beginning of this stage in the annual vegetation cycle of the grapevine is about six to eight weeks after budbreak. The exact time depends on the year-specific temperature development, the temperature totals reached at the respective location as well as the vine variety-specific growth under changing weather. Constantly warm temperatures with a good water supply accelerate the speed of shoot growth and thus the formation of the inflorescence (lat. inflorescence, depending on the country and region also flower, umbel, dotzen or geschein) on the third to seventh shoot node. Depending on the zonal climate, microclimate and solar radiation, flowering takes place in the northern hemisphere from mid-May to late July (in Central Europe, according to old winegrowers' rules, it starts on 24 June = St. John's Day, plus or minus eight days), in the southern hemisphere from November to mid-December. In contrast to many other flowering plants, the individual flowers of the vine are small, greenish-yellow and rather inconspicuous due to the absence of petals and show flowers. The individual grape berries form from the individual flowers when the fruit ripens.
There is a vast number of sources on the web where one can acquire knowledge about wine. But none has the scope, timeliness and accuracy of the information in the encyclopaedia at wein.plus. I use it regularly and rely on it.Sigi Hiss
freier Autor und Weinberater (Fine, Vinum u.a.), Bad Krozingen