Yes, July really was hot. But veraison still arrived late. What gives?

A month ago, I felt like I was tempting fate when I characterized the 2018 summer as "benign". Well, so much for benign. July was the hottest month we've ever seen here at Tablas Creek, with an average high temperature of 96.5 and an average overall temperature of 76.5.  Fourteen days topped 100, and only seven -- all toward the beginning of the month -- failed to get into the 90s. In terms of degree days, July saw us accumulate 844 degree days, fully 28% more than our average of 659. That's a big increase over what is already our hottest month:

2018 summer temps through July

Given the heat and the season, it really wasn't a surprise when I got an email from Neil on Monday with a photo of Syrah undergoing veraison. Veraison marks the point where a grape stops accumulating mass and starts accumulating sugar. More visibly, red grapes start their color change from green to purple, while white grapes take on more of a yellow tint. Both red and white grapes start to soften. [For more about what's happening chemically, check out this veraison post from the archives.] A few photos of Syrah clusters will give you a sense of what things look like now:

Veraison 2018 syrah 2

And:

Veraison 2018 syrah 3

It's worth remembering that most of the vineyard is still totally green.  Syrah is the first red grape to enter veraison, and I couldn't find even a hint of color on any of the others. And, that photo was from the top of our tallest hill, which is always more advanced than areas lower down both because they started earlier since their last frost was later, and because they're under more stress due to scarcity of water. But we know that once we see Syrah, the other grapes follow along in fairly short order.

One of veraison's principal values to a winery is as a marker: this landmark comes roughly six weeks before the onset of harvest, and gives us our best estimate for when harvest will begin.  But, of course, six weeks is a rough average, and can be influenced by the weather that we get in the interim, as well as by the amount of fruit the vines are carrying.  For example, in 2014 our earliest-ever veraison (noted on July 9th) was mitigated by a very cool August, and we started harvest 45 days later, on August 23rd. By contrast, 2016's first veraison was noted on July 13th, and combined with a very warm August to produce our earliest-ever beginning to harvest, just 36 days later. The last dozen years are compiled in the chart below, with each year linked to my blog post about that year's veraison:

Year First Veraison Noted Harvest Begins # of Days
2007 July 20 August 28 39
2008 July 23 September 3 42
2009 July 20 September 1 43
2010 July 30 September 16 49
2011 August 5 September 20 47
2012 July 25 September 5 42
2013 July 17 August 26 40
2014 July 9 August 23 45
2015 July 18 August 26 39
2016 July 13 August 18 36
2017 July 20 August 30 40
2018 July 29 ? ?

Using the range of durations between first veraison and first harvest (36 to 49 days) we can have good confidence that we'll begin picking sometime between September 3rd and September 16th. I'm guessing we start toward the early end of that range, given the warmth of the summer so far and the relatively moderate crop levels we've been estimating.

Given the heat in July, it's worth addressing why the vineyard hasn't caught up more from the roughly two weeks late it was after flowering. I'd point the finger at two culprits. First, we did catch up a bit; I'd estimate that we're more like 10 days behind than the two weeks we were in early July.  And second, grapevines photosynthesize optimally at temperatures between 30 and 35 Celsius (86 and 95 Fahrenheit). Two-thirds of our days in July got above 95 degrees, which means that the grapevines actually slowed down photosynthesis in the heat of the day as they closed the pores on their leaves to reduce dehydration.

What's next for the vineyard? We'll watch the different grapes go through veraison. Syrah will be followed by Mourvedre, then Grenache soon, and finally Counoise. In the cellar, we'll be getting the last of the year's bottling done so there's space in barrels and tanks for the coming crush, and starting the process of pulling out and cleaning all the tanks, barrels, and equipment we'll be using once harvest begins. Everyone will be storing up on sleep.

And now we know -- roughly at least -- how much time we have  left before everything shifts into harvest mode. Stay tuned.


A mid-summer vineyard assessment suggests 2018 is looking like a throwback to the 2000s

I feel like I'm inviting disaster just by typing this sentence, but it's been, well, benign so far this summer.  I got back from two weeks in Europe, some vacation and some work, to find a vineyard significantly advanced over where it was in the first half of June.  Vines that were just finishing flowering are now fully set, with early varieties nearly full-sized.  The Grenache, below, looks fully formed, though the grapes will continue to grow a little and there's no hint of color change yet:

Vineyard Summer 2018 Grenache

Fruit set looks good, with only minimal shatter, and the late rain that we received in March appears to have given the vines enough vigor to set a healthy crop.  We will surely be dropping some fruit this summer.

The vineyard looks vibrantly healthy, with even stress-prone varieties like Roussanne and Mourvedre still fully green.  This isn't a surprise; we've only had one day (June 22nd) top 100, and only 14 days reach the 90s.  That may sound like a lot, but the average nighttime low since May 1st has been 46 degrees, and a couple of days in mid-June didn't even make it out of the 60s. More measurably, in terms of heat accumulation (as measured in Degree Days at the weather station in our vineyard) we're still below our 20-year average, with May 18% cooler than normal and June just 5% warmer than normal.  I'm not sure if the health of the vineyard comes through in photographs, but it's (no pun intended) worth a shot:

Vineyard Summer 2018

Or, for another perspective, here's a shot from below the Counoise trellises, showing the clusters sheltering beneath their leafy canopy:

Vineyard Summer 2018 Under Counoise

How does this compare to other recent years, and what does it mean for harvest?  Well, our late-March budbreak, which kicks off the growing season, was about two weeks later than in most recent years, though more or less average looking at a 20-year perspective.  The weather since then has been quite a bit cooler than the years since 2012, but again, more or less average looking at the 20-year scale.  That's probably easier to make sense of in a graph.  First, the heat accumulation (in degree days) this year versus two averages: one of all years since 1997, and the other looking at just the recent warm stretch that began in 2012:

Summer 2018 Degree Days Through June

You can see that our recent years (in green) have been quite a bit warmer than the longer-term average (in blue), whereas 2018 (in red) is cooler.  That's perhaps even more dramatically illustrated by looking at 2018 in terms of percent difference from average.  All three months we've measured this growing season have been between 8.5% and 15.5% cooler than the 2012-2017 stretch:

Summer 2018 Degree Days Through June vs Normal

All this weather data just reinforces my thought that we're going to be seeing a harvest that's more like what we got used to in the 2000s (when we averaged 1069 degree days through June, nearly identical to this year's 1045) than what we've seen in the 2010s. The best comps to date are 2002, 2006, and 2009, all of which didn't see harvest begin until the first half of September. I'm not expecting veraison until we get close to the end of July.  Of course, there's still a long way to go, and there is a hot stretch forecast starting next week.  But we are at what's typically the hottest time of year, and it's still been moderate.  So far, so good.


Flowering 2018: Might We Be Seeing Our First Moderate Vintage of the Decade?

There are five viticultural markers that we use each year as markers: notable reference points that indicate where we are compared to other years.  These are, in order:

  • Budbreak (typically late March or early April)
  • Flowering (typically May sometime)
  • Veraison (typically late July or early August)
  • First Harvest (typically late August or early September)
  • Last Harvest (typically late October)

Budbreak gave us the first sign that we were going to see a later beginning than recent years.  Flowering, which we saw first evidence of in mid-May but which is still widespread as we get into the second week of June, is confirmation that we're looking at a growing season roughly two weeks later than what we've come to be used to since 2012. An example, from our Grenache block on Scruffy Hill in late May:

Flowering grenache on Scruffy Hill May 2018

If you haven't seen grapevines flowering before, you can be excused for finding it underwhelming.  It's not a showy process.  Still, the tiny white fuzz-like flowers that appear on the clusters are the first stage of development of the berries.  From this point on, if the berries are fertilized successfully, they'll grow in size and mass until veraison, at which point they stop growing but accumulate sugar and ripen the seeds within. 

During flowering, you hope for consistent, sunny weather, with only limited wind and no rain.  Cold or wet weather at this stage can produce incomplete fertilization, or shatter, where a cluster has a high proportion of unfertilized berries, looking snaggle-toothed and (often dramatically) reducing yields.  Some varieties, most notably Grenache, are prone to shatter, while others are less so.  This year, conditions have been good, and we are cautiously optimistic that shatter won't be a major issue. It's worth remembering that overall, conditions in Paso Robles are pretty benign compared to what grapevines face in most parts of the world.

2018 appears to be developing into something of a throwback. The rest of the years this decade have been pretty extreme at this stage.  In our warmer years (like 2012, 2013, 2014, 2016, or 2017) May has felt like early summer, with multiple days in the 90's and even low 100's.  In the chilly years (like 2010, 2011, and 2015) May has been more like April, with several nights dropping down into the 30's and most days topping out between the mid-60's and mid-70's.  What we're seeing is something more in the middle.  A quick line graph may help give you a sense. I've put the line for 2018 in red, to help it stand out:

Average Temps by Month 2010-2018

You can see that the 2018 trend line falls in the middle, in a space that's largely unoccupied (in May, at least) this decade. So, what does this mean for the rest of the growing season?It's too early to be particularly definitive.  It could develop into a year like 2015, where we ricochet between significantly warmer-than-normal months and significantly cooler-than-normal months.  It could build like 2012 from a cool early season to a scorching August.  Or it could settle in as a more uniformly cool or warm summer.  But we do have a not-insignificant portion of the growing season behind us, and at this point we're about 2% below our average number of degree days through June 6th, and 28% below our maximum to date (2014).  That cool weather, combined with a fairly late budbreak, suggests we're a couple of weeks behind most of our recent years, and unlikely to begin harvest before September.  Of course, there's lots that's yet to be determined.

At this point, we're happy to be most of the way through flowering in good shape, with the vines healthy from the March rain we received and the lack (so far) of heat spikes, at the roughly one-third point of the growing season.  And the vineyard smells great.

Flowering grenache on Scruffy Hill May 2018 2

We'll take it.


Assessing Winter 2017-2018 After March's Rainfall "Miracle"

At the end of February, we were looking at a potentially disastrous winter, with less than five inches of precipitation.  A major storm that arrived March 1st and dropped more than three inches of rain in 24 hours marked a major pattern shift, and the rest of March continued wet, finishing with nearly 12 inches of rain, our wettest March since we put in our weather station in 1996 and the sixth-wettest month in that time frame.  Although April was dry, we're in a much better place than it looked like we'd be.  For a visual sense of how the winter has shaped up compared to normal, I've put together a graph by month:

Rainfall Graph Winter 2017-18

You can see what an outlier March is, at 295% of normal.  Still, following six drier-than-n0rmal winter months, we will end this winter season at something like 70% of average, a total much more like what we saw during our 2012-2016 drought than the gloriously wet 2016-2017 winter:

Rainfall by Winter 1996-2018

Still, while it was a below-average rainfall winter, it's neither particularly troubling nor particularly unusual. It ranks 13th of the 22 winters since 1996. And it follows our very wet winter last year, which produced healthy vines and replenished our underground water sources. Historically, the first dry year after a wet stretch hasn't been particularly hard on the vineyard, thanks to the accumulated vigor and residual moisture, and has in fact produced some fabulous vintages like 1999, 2002, 2007, and 2012. 

It's also important to realize that the fact that the rain came late will have an impact on the growing season.  It's unusually green right now for mid-May, and that soil moisture is relatively plentiful close to the surface, easily accessible even to relatively young grapevines.  A few shots should give you a sense of what things look like. First, one from mid-April, before the Mourvedre vines in this low-lying area had sprouted:

Cover crop

Next, this photo of new growth in Grenache, from about a week back:

New Growth in Grenache

Because the rain came so late and we wanted to give the cover crops as much time as possible to build organic matter, we're behind in getting them tilled under. The vineyard at my parents' house is a good example; the cover crops are nearly as high as the cordons:

Haas Vineyard Cover Crop

The other implication of the late beginning of cover crop growth is that we weren't able to have the animals in the vineyard as much as we would have liked this winter, because there just wasn't enough for them to eat until the beginning of March. But we're planning to harvest the cover crops in sections of the vineyard where we weren't able to have them graze, to supplement their forage from unplanted portions of the property.

The late rain and the consistent sun in April has made for a spectacular wildflower season.  The mustard is blooming, adding an electric yellow blanket nearly covering the head-trained Grenache vines:

Mustard and Head trained Grenache

And, of course, the California poppies are the stars of the show.  Anyone who is planning a visit to Paso Robles this month is in for some spectacular scenery:

California Poppies

Big picture: we're feeling cautiously optimistic about things.  We've received enough rain to feel confident that our dry-farmed vineyards will do fine through the growing season, and in a concentrated enough period to have positively impacted our well levels. Budbreak was later than in recent years, and we're now largely through the frost season, with only one frost event (the morning of April 17th), which doesn't look like it did too much damage. The vineyard looks healthy.

Given where we were in mid-February, I don't think we could have asked for anything more.


A Late-March 2018 Bud Break Marks a Return to a "Normal" Spring

Two months ago, I was worried. January, normally our coldest month of the year, had seen only four nights drop below freezing. After one decent storm on January 8th and 9th, the rest of the month was dry, leaving us at just 20% of normal rainfall by month-end.  We ended the month with a week of sunny days, each topping out in the mid-70s.  The beginning of February was more of the same: ten days of sun in a row, each topping out between 75 and 81, with lows dropping down only into the 40s.  I was worried we'd see our vines start to sprout in February, setting the growing season off to an unprecedentedly early start and leaving us an unconscionably long period of frost risk.

Thankfully, mid-February brought a change in the weather pattern. Although the second half of the month remained dry (the 0.28" of rain is just 6% of what we'd expect from our second-wettest month) it got cold. We finished February with ten straight frosty nights, all but one dropping into the 20s. Only one of those days made it out of the 50s. And then, in March, it began to rain. We've seen fifteen days this month with measurable precipitation, totaling 11.94" for the month and bringing us to 16.54" for the winter, roughly 75% of what we would expect on this date. The vineyard has transformed, green cover crop springing from the ground as though it was making up for lost time. Now that we've passed the spring equinox and are in the middle of a week of sunny, increasingly warm weather, it's not surprising that I saw the first signs of bud break when I got out into the vineyard yesterday. Our viticulturist Jordan Lonborg provided photographic evidence with a photo of a sprouting Viognier vine this morning:

Budbreak 2018 Viognier

Budbreak, as you probably guessed from the name, is the period when the grapevine buds swell and burst into leaf.  It is the first marker in the growing cycle, a point when we can compare the current season to past years.  Upcoming markers will include flowering, veraison, first harvest, and last harvest.  And like harvest, budbreak doesn't happen for every grape simultaneously. Early grapes like Viognier, Grenache Blanc, and Vermentino tend to go first, followed by Grenache and Syrah, then later Marsanne and Picpoul, and finally, often a month after the earliest grapes sprouted, Roussanne, Counoise, and Mourvedre. And it really is just starting. Even Grenache, typically on the early side, was fully dormant everywhere except the very tops of the hills:

Grenache still dormant late March 2018

While this year is two weeks later than last year's budbreak, and a month later than our record-early 2016, it's only about average for what we'd have expected historically:

2017: Mid-March
2016: Very end of February
2015: Second week of March
2014: Mid-March
2013: First week of April
2012: Mid-April
2011: First week of April
2010: Last week of March
2009: Second week of April
2008: Last week of March
2007: First week of April

The timing of our cold and our rain was pretty much ideal. Grapevines (and all deciduous plants) pay the most attention to soil temperatures in deciding when to come out of dormancy. And wet soils retain cold better than warm soils. The double dose we received of cold and wet meant that despite the lengthening days, the vines' most important sensors were telling them that winter was still in effect, and sprouting would be a risk.  And, in fact, budbreak does begin our white-knuckle season, since while dormant vines can freeze without danger, new growth is susceptible to frost damage. April frosts cost us roughly 40% of our production in both 2009 and 2011, and we don't feel truly safe until mid-May. So, we've still got more than a month to go before we can relax, and it will be a few weeks before our later-sprouting varieties and our lower-lying (read: more frost-prone) areas are out enough to be at risk. 

But in general, if you could design a favorable winter weather pattern, it would look a lot like what we've seen recently. We'd ask for regular frosts and rain through the end of March, and then a switch to a warm, dry pattern thereafter. While we're always grateful for rain, since frosts tend to follow in the wake of frontal passages, the precipitation you get in spring storms isn't worth the risk of frost damage.  And the current long-term forecast calls for the high pressure system that has dominated our area this week, bringing sun and increasingly warm days, to persist for a while.

That's just fine with us. Now that the first vines have begun to sprout, we'll see the scene in the vineyard change rapidly. Please join me in welcoming the 2018 vintage.


Winter 2017-2018 remains one of our driest ever, but at least it's gotten cold again.

Last winter's gloriously wet January and February feels like a lifetime ago. The 4.32" of rain that we've received so far this winter is less than 14% of last winter's (near-record) 31.92" as of February 12th. Yes, last winter was extraordinary, but we're also at just 27% of the 16.16" we'd expect to have received to date in a normal winter.  National newspapers are speculating that despite relatively healthy reservoir levels in the wake of last year's snowmelt, we might be reentering drought conditions.  While things are nowhere near as bad as they were in 2015 or 2016, the California Drought Monitor recently upgraded much of coastal southern California to "Severe Drought" status. And as of now, we're looking at our first totally dry February since 1952. The winter so far:

Winter rainfall 2017-2018 mid Feb v2
Although we're all worried about the lack of rain, there is a more pressing concern. While December 2017 was very cold, with 20 frost nights, 2018 has been much warmer. January saw only five nights drop below freezing, and until two nights ago, February had seen zero, and 10 days in a row topped out at 75°F or higher.  A February 8th Wines & Vines article on very early budbreak in Ojai sent many of the Central Coast winery folks I know scurrying, asking neighbors if they'd seen any signs of the same in their necks of the woods.

So, Sunday night's chilly weather, and the forecast for a week of frosty nights, was a relief to us all.

Why would we worry more about the unusual warmth than the unusual dryness?  Well, too much more warmth and we would be looking at budbreak in February, which would be the earliest we'd ever seen. And early budbreak puts us at increased risk of damage from spring frosts, which can come as late as early May.  A bad frost typically costs us something like 40% of our production.  It's been a while since our last bad frost -- 2011 was our most recent, with other similarly bad ones in 2009 and 2001 -- but I'm not anxious to repeat the experience.  While a dry winter does have some implications on yields, typically it's not nearly as dramatic, at least not the first year of a drought.  It would be a different calculus if this winter had followed a string of dry years, but for now, our wells are in good shape and the vines strong from last year's ample winter rain.

Of course, it's not like we get to choose. And since the main determinant of budbreak is warming soil temperatures, the lack of rainfall and the warm weather both have roles to play in the timing of when the vines sprout.  Wet soils hold the nighttime cold much better than dry soils do, so a good soaking in the next few weeks would have the ancillary benefit of maintaining cool soil temperatures well into March. 

In any case, while we're all hoping for rain, we'll be looking forward each morning this week to seeing a frosty carpet. We'll take what we can get.


A cold, dry start to winter 2017-18, but a change is (hopefully) on the way.

It's going to be no surprise to most of you to hear that it's been a dry winter so far. You don't need to look any farther than the fact that much of the Central Coast has been dealing with fires at a time of year when we're more likely to be worrying about erosion. Even when we did get a little rain the week before Christmas, it served mostly to highlight just how unusually bare the ground was for late December:

IMG_6401

While the dry weather has meant pleasant afternoons that felt more like October than December, it was also very cold at night.  How cold?  In December, we saw 20 nights of frost at the vineyard.  Now a winter frost isn't unusual.  We typically get 30-40 nights a year that drop below freezing, and December is typically our coldest month.  Nor is it detrimental.  Grapevines benefit from being forced into dormancy, as it keeps them from expending energy they'll need in the spring on winter growth that won't help ripen grapes.

But it is unusual to see so many frost nights in a single month, and even more unusual for so many of those days to be warm.  The average high temperature in December was 68.9 degrees, and sixteen days made it into the 70s.  One day (December 13th) managed to set both Paso Robles' record high (73) and low (22) for that date.  What was the culprit?  Record low humidities, and a near-total lack of cloud cover.  Eighteen days saw relative humidity levels drop into the teens, with a stretch in early December where four days in a week saw levels in the single digits.  How unusual is that?  December 2016, which wasn't even all that wet, didn't see a single relative humidity reading as low as 30%.  Neither December 2015 nor December 2014 saw any days below 20%.  You have to go back to 2013, which for most of California's was its driest year on record, to find anything comparable, and even they only saw 11 days of relative humidity below 20%. No wonder our December brought us only a paltry 0.07" of rain.

The impact on the vineyard is likely to depend on what we see in coming weeks and months.  Typically at this point we'd expect to have accumulated 8.15" of rain. This year, we've only gotten 1.42", or 17% of normal.  Our cover crop has barely sprouted, and the soil is dry down through most of the root zone.  But there's still time.  Typically, more than two-thirds of our annual rainfall comes after the new year, and our two wettest months are, on average, January and February.  That said, there's no question that we're behind. Even with normal rainfall the rest of the winter, we'd only be at 73% of normal precipitation:

Screen Shot 2018-01-01 at 9.27.37 PM

There's no guarantee that we'll see normal rainfall the rest of the winter, either. The Pacific has settled into a mild La Nina pattern, which typically produces drier than normal winters in California.  That said, for the first time in over a month the near-term forecast is calling for some wet weather. The ridge of high pressure that has been responsible for our dry December is breaking down, and two small storm systems are forecast to impact the Central Coast this week. Even better, the following week is likely to see the storm track shift south enough for some potentially more significant rainfall.  Meteorologist John Lindsey shared the following graphic on social media, showing the two major model predictions of ten-day precipitation:

26198570_10156000551764487_5523753527846258315_o

While neither projection suggests we'll get drenched, both show an inch or two of rain as we enter January. That's not enough to get down deep into the zone where our dry-farmed vines' roots mostly are, but every bit helps.  At the least, it should get the cover crop germinated, and ensure that our flock of sheep, alpacas, donkeys, and llama has enough to eat this winter without our having to supplement.

Given how dry it's been so far this winter, we'll take whatever we can get. Fingers crossed, everyone, please.


Harvest at the Three-Quarter Pole: A Return to a More Normal Time Frame, with Solid Yields

Late last week, we welcomed our first major picks of Roussanne and Mourvedre into the cellar.

Roussanne in tank

Mourvedre in tankAnd with that, the home stretch of harvest officially began. There will be a lot of harvest chalkboards that look essentially like this one over the next couple of weeks:

Harvest chalkboard Roussanne and Mourvedre

Where we are, one week into October, is remarkably similar to where we'd expect to be, if we were predicting at the beginning of the year.  We're done with early grapes like Viognier, Vermentino, Syrah, Marsanne, and Grenache Blanc.  We're mostly done with what we consider mid-harvest grapes like Grenache and Tannat.  And we're just getting into our late grapes, Mourvedre, Roussanne, and Counoise.  Given that we're comparatively heavily planted in these late grapes, we still have more fruit out than many of our neighbors.  Still, we expect to be harvesting pretty steadily for the next two weeks, and to be done before the end of the month.  If this seems late, it's likely a matter of perspective, because most of our recent years have been early.  While 2013, 2014, and 2016 were all done by mid-October, our average finish date of harvest this millennium has been October 29th.

With the first complete blocks harvested, we've been able to get the animals back into the vineyard.  Right now, they're in the head-trained vines on our Scruffy Hill block, visible from Vineyard Drive if you're coming in from the south:

Animals back on Scruffy

Although we're where we'd expect to be in the harvest sequence, it hasn't always been smooth getting here.  Harvest began with a significant heat wave that sent temperatures soaring over 102°F nine days in a row.  We then got nearly three weeks of temperatures more than 5°F cooler than normal. In the last two weeks, temperatures have been more or less normal for the season, without any noteworthy heat waves, and with only one day significantly cooler than normal, a bizarrely chilly October 3rd where the sun didn't break through the fog until noon and the day topped out at 64°F:

Avg Temps 2017 vs Normal Sept Oct

For the month of September, we had 11 days warmer than seasonal averages, and 19 days cooler than average.  Even with the heat wave that began the month, our average high was 86.3°F, two degrees cooler than average. These cooler days allowed the vines to recover from the stress of their early-season heat wave, and allowed the cellar to free up tanks and get ready for the next push.  A graph of the harvest by week shows the ebb and flow. Normally, you'd expect a sort of bell curve, with thin tails at the beginning and end and the busiest weeks in the middle.  Not this year:

Harvest by Week

In terms of yields, with a significant number of grapes done, things are coming into focus.  It looks like yields are up from 2016, and a bit above average for the first time since 2012.  The varieties we've finished harvesting are up an average of 32.9%, with the most noteworthy recovery from Marsanne, whose yields had been so depressed by the five years of drought that we were getting less than one ton per acre last year:

Grape 2017 Yields (tons) 2016 Yields (tons) % Change vs. 2016
Viognier 18.9 14.2 +33.1%
Marsanne 13.8 4.5  +206.7%
Grenache Blanc 46.4 30.6 +51.6%
Picpoul Blanc ? 7.7 ?
Vermentino 22.2 19.0  +16.8%
Roussanne ? 47.0  ?
Grenache 73.1 58.8  +24.3%
Syrah 41.5 36.8  +12.8%
Mourvedre ? 62.7  ?
Tannat 18.3 12.3  +48.8%
Counoise ? 18.0 ?
Total so Far 234.2 176.2 +32.9%

Even with the higher yields, sugars are up a bit this year, which is a sign of the health of the vines.  Thank you, rainy winter!  The growing season, the yields, and the character and numbers of the grapes at harvest remind us most, so far at least, of 2005: also the first wet year after a string of dry years, with a long growing season and a relatively cool harvest period.  We aren't likely to go as late as we did that year -- November 7th -- but if we get a similarly robust vintage, we'll be happy. 

Meanwhile, we'll enjoy the last couple of weeks of grapes on the vines. By the end of the month, we'll have to wait another year for views like this:

Counoise on the vine early October


Why Paso Robles is So Well Suited to Late-Ripening Grapes

This morning, when I got back to the winery after a week on the road, my first order of business was to check in on how harvest was going. I was happy to learn that things picked up a bit last week. After more than two weeks of chilly fall weather, it had warmed back up, with eight days of perfect ripening weather: daytime highs between 83°F and 93°F, and lows between 41°F and 51°F.

And still, when I asked Chelsea how she was feeling, she responded, "this is definitely the first October 1st I can remember where we haven't been stressing about tank space."  Although harvest picked up from the glacial pace it was in mid-September, we are still waiting on most of our Marsanne, Roussanne, Mourvedre and Counoise.  Why? Blame the cold nights. Here's Neil, this morning, next to our first pick of Mourvedre. It was 52°F at 8:30am:

Neil looking chilly

We're used to this here, but most of the Mediterranean world is finishing up harvest about now. Beaucastel's Facebook page (for example) shows that they brought in their last fruit on September 29th:

It's not like this year is an outlier for us, either.  Over the last 15 years, we've averaged a last pick off the estate on October 29th, and our earliest-ever finish was October 7th in 2013.  Six times in those 15 years we were still picking in November. 

To explain why grapes take so long to ripen in Paso Robles, I'll have to detour briefly into some basic plant physiology. Bear with me here, or just skip to the end of the bullet points if you'd like the conclusions without the chemistry. There are a number of different processes which limit a grapevine's ability to photosynthesize at low temperatures. These include:

  • The tendency of plants to close their stomata (pores in the leaves) in response to cold, limiting respiration and the uptake of CO2
  • Carboxylation (sorry for the long, technical term) is the first stage of photosynthesis, whereby CO2 molecules are turned into an acid known as 3-PGA. Carboxylation efficiency declines as temperature declines
  • The electron transport capacity of plants is reduced at low temperatures
  • An enzyme known as Rubisco, essential to the first step of carbon fixation in photosynthesis, is inefficient at low temperatures

So, in essence, at cold temperatures, plants take in less CO2 and are less efficient in turning the CO2 that they do take in into the starches that fuel both plant growth and fruit ripening.  Grapevine ripening proceeds most efficiently between 30°C and 35°C (86°F and 95°F).  It drops dramatically below 25°C (77°F), and reaches zero at 10°C (50°F).  A summary graph from a technical paper published in Plant, Cell, and the Environment shows the combined effects pretty clearly:

Figure-7-CO2-saturated-maximum-rates-of-photosynthesis-meanSE-of-Semillon-leaves-as

For context, take a look at the temperature curve for the most recent 24 hour period:

Temperature C by Hour early October

You can see that while it did get warm, topping out around 30°C (86°F) yesterday afternoon, it only lasted until sunset just after 6pm.  By 8pm it was already down to 20°C (68°F). It bottomed out at 6.4°C (43.6°F) at 6am and wouldn't rise back up above 20°C until noon today.  So, over the last 24 hours, our vineyard spent 5 daylight hours over the 25°C temperature at which photosynthesis happens efficiently (2pm-6pm yesterday). Five other daylight hours (9am-1pm today) saw temperatures at levels where some photosynthesis can happen. Two daylight hours (7am-8am today) saw no photosynthesis at all because it was too cold.  And for 12 hours the sun was below the horizon. 

We are far from the only, or even the most extreme, location in Paso Robles.  The temperature grid from the Paso Robles Wine Country Alliance shows other areas that dropped near freezing last night.  Most show diurnal temperature swings of 40°-50°F. 

Temperature Grid October 2nd 2017

So, what does all this mean? That once you get into the end of the growing season here in Paso Robles, it's hard for grapevines to do too much photosynthesizing. That's a benefit, because you can get the last little bits of ripening on your late-ripening varieties slowly, so they continue to build complexity without accumulating too much sugar.  In general, the longer your grapes can stay on the vine before they get to the ripeness levels you want, the more complexity your wine has.  That's why a generally accepted bit of wine wisdom says that the best examples of different grape varieties can be found at the northern limit of their ripening range. So, the best Sauvignon Blancs tend to come from the Loire, and not Bordeaux. The best Pinot Noir tends to come from Burgundy, and not the Languedoc.  And the best California Chardonnay tends to come from cool coastal pockets where the fog slips in from the Pacific, not from the Central Valley.

Of course, at some point, you do need to get things ripe.  Grapes that don't make it to good ripeness produce wines that are green and bitter: no one's idea of a pleasurable drink. But here too Paso Robles has an advantage: that we don't tend to get our first serious rain until mid-November.  If we need to wait, we wait.

Hopefully, this particular waiting game is over for a while. But if it's not, I'm still confident we'll be OK. Thanks, Paso Robles.


A cool interlude slows down Harvest 2017 as we reach its mid-point

Ten days into the 2017 harvest, our winery crew was looking harried. Seven consecutive 105°+ days produced an avalanche of fruit. Right as we were genuinely wondering what we would do if the heat kept up, the weather broke, and now, two weeks later, it still hasn't really put itself back together. Take a look at our high temperatures compared to seasonal averages:

Avg Temps 2017 vs Normal

Since the heat wave broke on September 4th, we've had only two days above our seasonal averages, and the average high (84.1°) has been more than five degrees cooler than we'd expect.  At first, there was a bit of a backlog of fruit ready to pick, but by the time we got to this past weekend, we were back in waiting mode:

Harvest chalkboard interlude

To have a slower period like this in mid-September is a luxury. We've been able to free up tank space ahead of the next wave of fruit we know will be coming, and we've been able to spend a lot of time out in the vineyards testing, waiting for the right moment.  And the pace really has slowed.  After 110 and 142(!) ton weeks to start harvest, last week saw just 54 tons arrive at the winery, and we've only picked 16 tons so far this week.  

So, with 322 tons received, we're at or just past the mid-point on our harvest, based on our estimates. And now that we've finished picking some of our early grapes, it gives us a chance to assess where yields are compared to what we'd expected and compared to other years.  And things look solid. The 19 tons of Viognier we picked was up about 33% compared to 2016.  Vermentino (22 tons) is up about 15%. We're not quite done with Syrah, but the 33 tons we've picked is close to last year's 37 tons. The 4.7 tons of Marsanne we picked is almost identical to last year's 4.5 tons, though still very low.  Overall, I'm guessing we end up slightly up from last year's numbers, but not by much.

The cellar has been its usual dance, with fruit coming in (albeit at a more moderate rate) while other tanks are fermenting away and yet others are being pressed off to make space. One fun consequence has been that we have Grenache Noir, Grenache Blanc, and even Grenache Rose fermenting at the same time.  Check out the colors:

Three colors of grenache

The colors aren't only inside the winery. Outside the vineyard, it's starting to look -- as well as feel -- like fall.  As the vines start to lose chlorophyll, the autumn oranges and reds come out.  It's more dramatic on some grapes than others, but Syrah and Mourvedre are particularly lovely.  This Mourvedre vine is from right outside the winery; anyone coming to visit in the next few weeks should see a scene very much like this:

Mourvedre head trained

So, where are we, at harvest's mid-point?  Largely done with our Patelin picks, with the exception of some Mourvedre and a little Grenache and Syrah. Off our estate, we're done with our early whites (Viognier, Vermentino, Marsanne) and mostly done with Grenache Blanc and Syrah. We've made a start on Grenache, and today got our first Tannat into the cellar. Next week, we'll turn in a serious way to Grenache, and maybe get started on the later-ripening Roussanne, Mourvedre and Counoise.

It feels somehow appropriate that we've filled in the left-hand column of our harvest chalkboard. With the forecast set for it to warm back up next week, it feels like we can dispense with the halftime entertainment and get on with the second half.

Chalkboard Sept 21

We'll be back for the second half kickoff, after this break.