On any given day over the past several months you could pass by a local vineyard and find large crews out working amongst the seemingly dormant vines. Just what were they doing?
Vineyard pruning, while not perhaps the sexiest of topics, is an important part of the process. We recently caught up with St. Supéry’s vineyard manager Josh Anstey, who was kind enough to answer a few of our questions on the topic…
CB: Generally speaking, what is the approach you take at St. Supery to vineyard pruning? What impact does pruning have on the end-product that will eventually wind up in the bottle?
Anstey: It always depends on variety, soil, aspect, terrior in general and what we want to achieve. Pruning has HUGE impact, sets up vine for coming year and really for decades. It dictates canopy shape and really number of buds and therefore yields for the year.
CB: In general, when does pruning happen in Napa Valley vineyards and at St. Supéry specifically?
Anstey: You can prune anytime…after leaves drop VERY typical (when dormant all carbohydrates stored in woody parts) we wait as long as we can (January, February, March)…delays bud break and better for a fungus called Eutypa lata…less spores late in winter and “juices” start flowing and pushes spores always from pruning wounds.
CB: Are there differences in what varietals get pruned when? If so, please explain.
Anstey: Varieties vary for sure, our Sauvignon Blanc for example we are looking for a mix of shaded and open fruit zone, reds for us typically we want open and uniform fruit zone.
CB: How about differences in terms of vineyard location (i.e. valley floor vs. higher elevation)?
Anstey: Vineyard location also very important, hill side = less vigor, you want less buds and always balance of soil and crop load
CB: Some vineyards appear to intentionally leave the vines long at the end of each vineyard row, while others leave the trimmed vines in between the vineyard rows after they’ve been cut. What’s the idea behind each of these methods? What are the benefits?
Anstey: Some places take it out, either they don’t want to cultivate with a mower/flail, or can’t depending on spacing and machinery they have. When left in the middles of rows we flail and incorporate all this organic matter back to soil. We are very Sustainable at St. Supéry and soil health is always key. Being officially certified as “Fish Friendly” and “Napa Green” the healthier our soil the better = less fertilizer and better vine health and therefore better wine. France typically (in Bordeaux, narrow rows and harder to flail) pulls out canes and burns, due to possible inoculum on this plant material. Some people in Napa do this as well (many also chip in a chipper), our disease pressure in WAY lower then France and I can’t see this as justification here…
CB: Thanks for the time and insights Josh, cheers!