Those of us in the wine business are sometimes asked questions that catch us off guard. For example, “How many bottles of wine come from a grape vine?”
This type of question is hard to answer because winemakers think more in terms of production-specific measurements, such as tons per acre; gallons per ton of fermented wine; cases per ton of finished wine or other benchmark statistics.
Even with most of these statistics, there are no universal standards because there are so many variables that influence the conversion of grapes to wine.
Starting in the vineyard, the yield of a vine in terms of cluster weight depends upon the grape varietal and the age of the vine. Also, some rootstocks and clones generate higher cropping levels than others. Different spacing in the vine rows affects the number of vines per acre, while the number of spurs per vine determines the cluster counts per vine.
Then there are all the variables in winemaking, such as how much juice is produced from different grape varietals and how all of the fermentation, aging and bottling techniques affect the finished wine production from a ton of grapes.
Most importantly for our statistics at Robert Craig, there is a huge difference in the yields of grapes grown on hillside vineyards versus vineyards on the valley floor. As a result of soil drainage from steeper hillsides and more austere growing conditions, mountain vineyards, as a rule, yield crop levels that are about 65% of those from the valley floor.
All that said, I’ve decided to try coming up with answers to commonly asked questions about grape and wine production. For this purpose, I’ve focused on Napa Valley Cabernet Sauvignon – which of course is the wine we make – assuming mature vines with average yields.
I’ve also elected to use vine spacing of 5 x 8 feet, which is the typical spacing in our vineyards. This spacing on a cordon-trained vine results in about 12 fruiting spurs, with 2 clusters per spur, or 24 clusters per vine. For tighter spacing, the pounds per vine are less. The numbers for cases/bottles of wine are for finished wine after the racking, topping and bottling losses.
I hope you enjoy this Q&A. Use it as a way to impress your friends! When you look at a vine, check out the varietal, spacing and pruning. Then say, “That vine looks like it produces about 2.5 bottles of great Napa Valley Cabernet Sauvignon.” You will be close enough!
Valley: 4 tons – Mountains: 2.5 tons
How many pounds of grapes per acre?
Valley: 8,000 lbs – Mountains: 5,550 lbs
How many pounds of grapes per vine?
Valley: 7.34 lbs – Mountains: 5.05 lbs
How many pounds per grape cluster?
Valley: .31 lbs – Mountains: .21 lbs
How many pounds of grapes in a case of wine?
How many pounds of grapes in a bottle?
How many bottles of wine per vine?
Valley: 2.94 bottles – Mountains: 2.02 bottles
How many bottles of wine per cluster?
Valley: .12 bottles – Mountains: .08 bottles
How many gallons of wine in a barrel?
How many cases of wine in a barrel?
How many cases of finished wine in a ton of grapes?
How many bottles of wine in a ton of grapes?
After all this talk about numbers, the real question is – do you like the wine, no matter how many tons, pounds, barrels or gallons it takes?
Enjoy in good health,