Harvesting the grapes

The harvesting of wine grapes (Vintage) is one of the most crucial steps in the process of wine-making. The time of harvest is determined primarily by the ripeness of the grape as measured by sugar, acid and tannin levels with winemakers basing their decision to pick based on the style of wine they wish to produce. The weather can also shape the timetable of harvesting with the threat of heat, rain, hail, and frost which can damage the grapes and bring about various vine diseases. In addition to determining the time of the harvest, winemakers and vineyard owners must also determine whether to use hand pickers or mechanical harvesters. The harvest season typically falls between August & October in the Northern Hemisphere and February & April in the Southern Hemisphere. With various climate conditions, grape varieties, and wine styles the harvesting of grapes could happen in every month of the calendar year somewhere in the world. In the New World it is often referred to as the crush.

The majority of the world's wine producing regions lie between the temperate latitudes of 30° and 50° in both hemispheres with regions lying closer to the equator typically harvesting earlier due to their warmer climates. In the Northern Hemisphere, vineyards in Cyprus begin harvesting as early as July. In California some sparkling wine grapes are harvested in late July to early August at a slightly unripe point to help maintain acidity in the wine. The majority of Northern Hemisphere harvesting occurs in late August to early October with some late harvest wine grapes being harvested throughout the autumn. In Germany, the United States and Canada, ice wine grapes can be harvested as late as January. In the Southern Hemisphere harvest can begin as early as January 1 in some of the warmer climate sites in New South Wales, Australia. The majority of Southern Hemisphere harvesting occurs between the months of February and April with some cool climate sites like Central Otago, New Zealand picking late harvest wine grapes in June.

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Wikipedia