Once all the grapes are off the vine and the wine is done fermenting and pressed off, the winemakers and vineyard managers can breathe a sigh of relief and toast to another vintage in the bag (er, barrel). However, that does not mean they can take a break or go on vacation just yet. The work is not over for another month or two.
In the cellar, all the finished and pressed wine needs to be either put to barrel or bottled. If being put to barrel, the wine chemistry needs to be adjusted, if necessary, in regards to pH and free SO2 content, in order to keep any bacteria or oxidation from forming (see the Harvest Series blog 9 on laboratory analysis). If the wine is undergoing malo-lactic fermentation, it needs to be closely monitored for spoilage or oxidation, as sulfur dioxide will impede the process, and too much oxygen exposure will spoil the wine. For that reason, the barrels must be kept completely full of wine. Since wood has pores, there is a certain amount of evaporation that happens through the pores of the barrels, so a regular topping of the barrels with similar wine must be done to keep them full. Once lab tests show that malo-lactic fermentation is complete (usually a few weeks to a few months), the wine can then be better protected with SO2. High pH can be adjusted to a stable level with tartaric acid added to the barrels and stirred in. Once all lots have been properly adjusted, they can be left to age with minor SO2 adjustments and topping until ready to bottle. If the wine is to be bottled without seeing oak, it can be prepared for bottling shortly after fermentation is complete (see the Bottling blog for details on that).
On the crushpad, crush equipment can be cleaned thoroughly and put away or covered until next harvest. This is also a good time for maintenance or repairs on the machinery so that it’s ready for next season.
In the vineyard, the leaves are turning colors and dropping from the vines. Any undesirable clusters can be removed from the vines and from the ground to avoid spreading disease or pests. Once fruit is removed from the vines, they begin to shut down and go dormant for the winter. Before dormancy sets in, it is a good practice to give the vines one more dose of fertilizer and a good watering. This is helpful to the vines when they start to come out of dormancy in the spring, and the roots begin to move water and nutrients through the vines again, and gives them a healthy start. The year’s canes (fruit-bearing shoots that have grown out of the vine that year and lignified to wood) are pruned off, down to the spurs (spur-like protrusions that the shoots grow from). Winter cover crops are sown between and beneath the vines. Cover crops are alternate crops, usually grasses, that provide nutrients and nitrogen to the vines in the growing season.
In the vineyard shop, just as on the crushpad, machinery is cleaned and maintained, repaired if needed, and put away for the next season.
I hope you’ve enjoyed the harvest series. Cheers to another great vintage in wine country!