Where and when the Riesling vine originated is not clear. Germany is commonly seen as Riesling's homeland. The oldest documents mentioning Riesling are from 1435 (Rheingau) and 1465 (Mosel)1.
Riesling thrives in cooler climates, for which it is well equipped. The vine's hard wood can withstand cold winters. Cooler growing temperatures mean that the grapes can keep their acidity for longer. If cultivated in hot climates Riesling ripens too quickly and loses its acidity and the resulting wine tastes flabby.
Although Riesling is grown in almost all wine producing regions, it needs a particular microclimate of long hours of sunshine at moderate temperatures during the day (in order to ripen satisfactorily) and cool night temperatures (to maintain its refreshing acidity).
Continental climates like those in Germany, Alsace or Austria have moderately warm summer days. Equally important are the long hours of daylight these countries provide due to their northerly location. In warmer wine regions, like those in Australia, Riesling thrives only on elevated, cooler vineyard sites. The relatively hot wine regions of Clare Valley or Frankland River in Australia are therefore best known for their crisp Riesling wines.
In the U.S.A. Riesling can be found in California, but it is better know in cooler regions such as Oregon, Washington and particularly in New York's Finger Lakes region.
