Most vinifera grapevines that I grow have a maximum two clusters per shoot. So from a fruiting bud, the shoot (it is later called a cane) that emerges will have fruit clusters. Normally, you will have two clusters that are on the fruiting canes and that is it! Since my Petit Verdot is on its third leaf, we have a full trellis of fruit. As I was observing the fruit a few weeks ago, I noticed that some of the fruiting canes had 3 clusters. I thought, wow, this must be an aberration! So I gave a call to my friend Ron Barrett from Kinkeadridge in Ohio. Ron used to manage the Erath vineyards in Oregon before moving to Ohio to challenge himself with growing vinifera in a colder climate. Ron grows vinifera and makes some damn good wine. Ron said it is common to have three clusters on Petit Verdot. Here is a picture that may show on close examination the reality of three clusters.