Once planted, grape vines take about three years to begin producing fruit suitable for making into wine. Once established, the vines can produce fruit for many years. Some hardy vines are still producing a century after their first harvest. Vineyards are farms that follow a continuous cycle of preparation, production and harvest. Beginning in spring the cycle proceeds roughly as follows:
March/April – The buds on the vines begin to leaf. This is called bud break. With the re-introduction of leaves, photosynthesis begins to nourish the vine. Frost is a threat to the vines at this time. Should the forecast predict freezing temperatures, sprinklers may be used to provide a protective insulating layer of ice around the tender buds.
May – The vines begin their subtle bloom. The bloom is usually complete by late may and is followed by the fruit set. The farmers check the nutritional state of the vines and plan for the application of fertilizer. The new vertical shoots are positioned correctly by the use of the trellis while rainfall and soil moisture are carefully monitored at this time.
June – Fertilizer may be applied this month and the moisture levels in the ground are watched closely. If needed, drip irrigation is used to water the soil around the vines. Leaves are thinned, improving ventilation around white grapes and boosting the color of the reds. The grape clusters are thinned out if the crop is bountiful. Thinning is done to improve the overall quality of the grapes.
July – The ripening begins, “white” grapes change color from green to yellowish-green and the “reds” turn from green to purple. This is called veraison, and usually starts towards the end of the month.
August -The veraison begun in late July completes. By this time the berries have nearly doubled their size and developed deep color. In some vineyards, irrigation may be reduced or stopped. Attention now turns to the sugar levels in the grapes.
September - This is a wonderful time in the vineyard. Harvest is approaching and the weather is fantastic. The sugar level are monitored extremely carefully and the wine makers and growers judge when bring in the harvest.
October – This is the month when the bulk of the harvest takes place. Some vineyards harvest by night to avoid having the grapes off the vine in the heat of the day. When the grapes are harvested the vines get a good soaking of water to help replenish nutrients in preparation for the following year. Cover crops may be planted and there may be some fertilization of the vines depending on their needs.
November – The last of the harvest is completed by the middle of the month.
December – Pruning of the vines might get underway. Tests are performed to predict how fruitful the next buds will be. The degree of pruning depends on these tests.
January – Wet weather and grey skies accompany the workers that aggressively prune the vines. The discarded vine clippings get mulched as the cover crops are mowed.
February into March – Pruning wraps up and the cycle starts again.