So you’re convinced that healthier soil means higher wine quality?
At Groth’s high level of winemaking, we’re looking for that unique vineyard expression. If the vines are fighting disease and are slow to ripen, we’re not going to get that pure expression of place.
You’ve said that you’re aiming for vine balance. What does that mean and how do you achieve it?
One thing I’m looking at is cane length. In a balanced vineyard, the canes stop growing on their own at four to five feet, adequate to ripen two clusters of fruit. If you leave too little wood, you have big, long canes that you have to hedge. The vine doesn’t want to stop growing, but it needs to stop and focus on ripening the fruit. If you have too many spur positions on the wood, you won’t have enough leaf surface to ripen the fruit. You’ll have a lot of crop but it won’t be good.
Valley floor vineyards like ours are typically fertile, with lots of soil moisture. For us, a quadrilateral cordon works best. We leave a lot of wood on each vine, which can push a lot of shoots to match the power of the site. So we see a natural cessation of vegetative growth, with no need to hedge except in a wet year. To me, that’s farming appropriately for the site. You couldn’t put quadrilateral cordons on a hillside vineyard. The soil couldn’t support that much vine.
So quality for you is not about tons per acre?
It’s totally site specific. There is no magic number. From a well-managed valley floor vineyard, you can see up to six tons per acre of optimally ripe fruit. You won’t see that on a hillside. People have a tendency to associate quality with the 1-1/2 tons per acre that they get on a hillside. If we dropped to that crop level on the valley floor, the wine wouldn’t be any better. We would just be dropping fruit.
If we’ve done our planting correctly—chosen the correct rootstocks and the right trellis and the spacing to set us up for balanced vine growth—what we should see is less need for interference. We won’t need to remediate, running a hedger or dropping crop. That means lower labor costs, lower fuel costs, fewer tractor passes, less compaction. It’s all of those little things that get you to the end goal.
Copyright 2017 Wine Institute