Our original vineyard planting has 16 rows, planted along the contour, spanning a section of soil that gets shallower and rockier as one moves down slope. The 8 rows in the rockiest, shallowest part we refer to as the “Lower 8 rows”. In our first 2 vintages we have seen a pronounced difference in vine growth habit, crop yield, berry color, and taste difference here. These taste differences have us excited. The yields in the Lower 8 are 30 to 40% less than the yields in the upper eight rows. Though no farmer wants to have lower yield, beyond the flavor differences, there is one immediate compensation: the foliage growth is so much slower in these vines that they require much less management. We do less shoot thinning, less hedging and less leaf pulling. While we really don't have any large sections in our vineyard on vigorous heavy clay soil's, there are a few pockets where the soil is a little deeper and richer and when working with those vines it can feel like a wrestling match. In the lower 8 it's more like a dance.
I'm sure as we become more sophisticated farmers we may find ways to improve that yield, even though we avoid chemical fertilizers and irrigation, things we know can boost yield, but which also are thought to limit the expression of land in the fruit and wine (aka terroir). But in reality, we are not too focused on yield, rather, we want balance: limited external inputs and exports of chemical/sediment/nutrients (pollution), and we want to let the vines grow optimally, and to harvest their best fruit.
One technique which we ARE beginning to explore is increasing "planting density". Our original planting had a vine every 4 feet, but when we expanded the lower eight rows last year we planted one vine every 3 feet. European growers use this technique quite a bit, as do some of the cutting edge growers in Virginia.
We will see what happens. We will make wine from what happens.