The delayed 2019 Harvest begins slowly, but we can feel the wave building

This is the time of year when everyone in Paso Robles begins every conversation with "so, how's harvest coming for you?" Typically, they're asking if you've begun, and if so, if you're far enough in to have a sense of how things will look. And we have begun, although only a little, and just two grapes. But even these grapes give us useful data points as we look to compare the 2019 harvest with other recent vintages. And one thing is clear: there's a lot more on the way, soon.

We began harvest on August 29th with a pick of about five and half tons of Pinot Noir from my parents' place in Templeton. As we typically do for the first pick, the whole cellar team goes out and works alongside the vineyard crew. Perhaps that's why Vineyard Manager David Maduena, overseeing his 26th(!) harvest here at Tablas Creek, is looking amused:

The grapes look amazing. It's remarkable how little stress the vines appear to be under, at a time of year when they're usually starting to look a bit ragged. That's a testament to the ample and distributed rainfall we got last winter, and to the relatively moderate summer we've seen. Even with the past four warm weeks (average high temp: 92.4°F), we've only seen eight days this summer top 100°F, with a high of 103.5°F. That may sound like a lot, but it's well below the average here, and the nights have remained cool: the average nighttime low over the last four weeks was 54.9°F, and every one of the seven 100+ days saw nighttime temperature drop into the 50s. A few photos should help give you a sense of the health of the vines. First, the Pinot block. Everything is green, not a hint of red or yellow to be seen in the leaves:

And it's not just Pinot. Check out this photo looking out over two blocks that would normally be showing signs of stress in early September: a hilltop Grenache block in the foreground (still only partway through veraison) and the dry-farmed "Scruffy Hill" block on the other side of the creek. Both are still vibrantly green:

But for all that we're still recovering from the delayed beginning to the growing season, we're making up time fast. The conditions (mid-90s highs and mid-50s lows) have been absolutely ideal for grapevine photosynthesis to proceed with peak efficiency. And we've definitely caught up. In my veraison post on August 6th, I looked at the 36-49 day range that we've observed between first veraison on the estate and first harvest and made a prediction that we'd start between September 4th and September 17th. As it turned out, 2019 will tie for our shortest-ever duration between veraison and harvest, and at 3am yesterday (September 4th) the team convened at our oldest Viognier block to kick off the 2019 harvest. Shepherd/Videographer Nathan Stuart was there to capture it. Definitely turn on the soundtrack for this one:

If you haven't been a part of a night pick, it's a memorable experience. There's a camaraderie in the shared work, the early start, and the silence that surrounds you. Until, of course, the lights go on and the tractors rev up, and then it's go time.

We didn't pick that much, just eight bins (a little under four tons) from the top of the block. The bottom of the same hill was enough behind the top to make it worth waiting until next week. But after having run numbers on most of the early-ripening grapes, we know that things have moved enough that it's likely we'll see more Viognier as well as our first Syrah and Vermentino next week. And then, we'll be in the thick of things.

How does this compare to last year? With only two data points, it's hard to say. We picked Pinot quite a bit earlier this year than last (August 29th vs. September 10th) at similar numbers. But we picked the first Viognier from here bit later than last year (September 4th vs. August 31st). Yes, the regions are different, but not wildly so. Instead, I think that the Pinot vines were delayed last year by the swings between cool and hot which we largely avoided this year. In 2019, the two regions have accumulated almost exactly the same number of degree hours compared to average: Templeton Gap 2249 (0.4% above average) and Adelaida District 2430 (1.2% above average). By contrast, to this point last year, we were 9.6% above average here at Tablas Creek, and 5.9% above average in the Templeton Gap. So, why are many of our grapes coming in earlier despite the cooler year?

To understand why, it's important to know what degree days (or degree hours) is measuring, and how it does and doesn't correlate with how grapevines ripen. Degree days measure the number of hours that temperatures spend above an arbitrary line, which corresponds roughly to the point at which plants start photosynthesizing. But in a year like 2018, when we had cool stretches interspersed with one long scorching hot stretch it's important to remember that neither cool nor very hot temperatures are ideal for grapevine photosynthesis. Instead, grapevines photosynthesize optimally in consistent very warm (but not hot) weather. And we've almost entirely avoided those hot days this year. Last year? Not so much. We saw 25 days that topped 100°F, including ten hotter than our hottest day this year (103.5°F). At those very hot temperatures, grapevines close the pores in their leaves to protect themselves from dehydration, slowing their photosynthetic capacity. This year, it's been all systems go.

It may be early in the harvest season, and we may only have brought in two grapes, but all signs point to it getting busy soon. If you see a winemaker out at a restaurant in the next few days, you might want to wish them well. Because you may not see them again until November.