Our vineyards and winery are perched on rolling hills that look directly onto San Pablo Bay. There is nothing between Buena Vista Winery and the Bay except flat marshlands. While most Carneros vineyards are more shielded from the wind, Buena Vista vineyards have unobstructed exposure to the incoming wind and fog – the most defining characteristics of the region.
While Carneros shares a climate cooled by coastal fog intrusions with other regions, the defining factor that sets us apart is wind. Every afternoon, the relentless “Petaluma Express” blows in from the coast, lowering the temperature in the vineyard and extending our growing season. Lowering the temperature slows photosynthesis, prolonging the ripening season and allowing extra flavor development while slowing the loss of precious acidity. The result – even with the sun shining, the grapes develop sugar and flavor more slowly than in a comparable area with less wind. The longer a grape is allowed to hang on the vine before picking, the more flavor it will have. The same fog that shrouds the Golden Gate Bridge floods inland at night maintaining the cool morning temperatures and delaying warming of the vineyards (sunlight is the “on switch” of photosynthesis and temperature is the “gas pedal”). Again, the vines have less time each day in which to ripen the grapes, forcing longer hang time on the vine.
With all of this delaying, you may wonder how does anything ripen. The answer, strangely, is still San Pablo Bay. This large body of water is a giant cooling unit and an insulator. Carneros is generally cooler that Napa and Sonoma proper because it is closer to the water. But water is also an insulator, meaning that it keeps overnight lows a bit warmer and daytime highs a bit cooler. The nearby water moderates the climate of Carneros, making it less extreme and creating warmer winters and cooler summers.
The warmer winters mean that Spring often arrives earlier to bring the vines out of dormancy. The more moderate summer temperatures combine with cooling fog and the cooling of the wind to delay ripening and harvest. The net result is that the overall growing season in Carneros is the longest in the area. Carneros vines spend less time each day ripening while the long season gives them more days to ripen. This longer growing season equates to more varietal flavor development in the grapes.
