Harvest has just been completed and the winemakers and their crews are now letting the wines age in the barrel room. In the vineyard, the vines are going through their crucial transformation into dormancy. As the temperatures get colder and the days shorter a physiological change occurs within the vine that allows it to endure the cold months that winter has to offer. The leaves change color and fall, a process called senescense. At this point the vines have stopped producing energy through photosynthesis. The plants will rely solely on stored energy it has gathered throughout the growing season in the roots, trunk, and branches. The stored energy will be crucial when converting from dormancy to bud break when spring time temperatures are on the rise.
Chemical changes occur within the vines during the cold, dormant months. Water inside the plant’s cell tissues can freeze causing the cells to burst and damage the vine. The vine develops a natural defense to this threat. The vine actually stops the uptake and absorption of water from the root system and transfers water out of the plant cells and into the inter-cellular area where it can freeze without causing damage.
Pruning will begin during these dormant months with the cuttings being raked into the rows and eventually tilled into the soil. Pruning sets the stage for Harvest even though it may be more than seven months away.
In general, growers cut away most of the canes left over from the previous year’s activity, leaving a few which will, in turn, produce shoots which grow into canes which will eventually produce fruit.
The idea is to cut away enough of the vine so its energy can be focused on ripening fruit efficiently.
As spring continues temperatures increase and days become longer. The soil warms up and sap begins to flow through the trunk and canes of the vine, nodes on the canes will begin to swell and buds will emerge. Soon they will break open and shoots will begin to grow upwards. This is a time of transformation in the vineyard, it comes alive. As the changes occur and life emerges the transformation continues. The grape flowers will each produce fruit if pollinated successfully. Pollen grains from the male, stool-like stamens will drift over to the bean bag-like ovary 1/8” away and germinate a grape. Wind, rain, or cold weather can disrupt the stamens from the process.
By the time the flowering is complete in July, growers have a good idea about the size of their potential crop. Many clusters will be cut or dropped from the vines toward the end of the summer to ensure the vine will focus its energy efficiently and ripen grapes on time. Sometime in August, red grapes begin to change color from green to purple (veraison) and the stage is set for harvest. Verasion is a magical time in the growing year. Over about a week, hard, green fruit change to deep purple. Verasion tells the grower that the ripening process has begun. Grapes change color only when a certain level of sugars is reached.
Fall is synonymous with harvest. Harvet is the culmination of a year’s worth of hard work and patience and it can also be a time to test the growers nerves. Ever since veraison the amount of acid has been dropping and thesugars have been on the rise. At one point the grapes will become “ripe” although personal taste and the style of the finished product varies amongst winemakers. Frost and rain are major concerns during this time. If rain soaks the fruit, rot may spread throughout the cluster and the harvest may be compromised. Once the fruit is finally brought in to be crushed the grower can breathe easy and pass the torch on to the winemaker. As harvest draws to a close, the leaves will change from green to yellow to golden red and fall to the ground. By the time Thanksgiving rolls around the vineyard will look a lot like winter.