Why Calcareous Soils Matter for Vineyards and Wine Grapes

What do regions like Champagne, Burgundy, Chablis, Tuscany, Alsace, the Loire, Saint-Emilion in Bordeaux, and Chateauneuf-du-Pape all have in common? They've all got soils that are variously described as chalky, decomposed limestone, and calcareous. In chemical terms, all are high in calcium carbonate, the basic building block of marine life.

So too does much of the Paso Robles AVA, particularly the sub-AVAs of the Adelaida District, Willow Creek District, Templeton Gap, El Pomar, and Santa Margarita Ranch. In all these regions, if you find a road cut, the rocks will be chalky and white, and if you dig into them you'll find marine fossils, from fish scales to oyster shells to whale bones. Yes, ten million years ago, our part of Paso Robles was under the Pacific Ocean. This makes our land, in geologic terms, relatively young. When they make their way to the surface, the rocks are creamy white and surprisingly lightweight:

What Are Calcareous Soils?
Calcareous soils are formed from the crushed up and decayed shells and bones of sea creatures. These layers settle down to the bottom of shallow oceans and, depending on how much heat and pressure they're subjected to, can be as soft as talc or chalk, or as hard as limestone or even marble. Of course, in order for plants to be able to access the calcium carbonate, it needs to be friable: soft enough for roots to penetrate. This means that even when you hear about a region having "limestone soils" the value to the plants isn't in the limestone itself, but in areas where the limestone has decayed into smaller particles.

From a grapevine's perspective, it doesn't really matter if the calcareous soils come from the erosion of limestone (as in Burgundy) or whether they never quite got heated and compressed enough to become rock (as in Paso Robles). The net impact is the same. There are four principal reasons why these soils are so often good for wine quality.

In winter, the calcareous clay absorbs moisture, turning dark.  Note the roots that have pene- trated between the layers of clay.

Benefit 1: Water Retention & Drainage
Calcium-rich clay soils like those that we have here have water-retention properties that are ideal for growing grapevines. Some water is essential for cation exchange -- the process by which plants take up nutrients through their roots. But grapevines do poorly in waterlogged soils, which increase the likelihood of root disease. Calcium-rich clay soils have a chemical structure composed of sheets of molecules held together in layers by ionic attractions. This structure permits the soil to retain moisture in periods of dry weather but allows for good drainage during heavy rains.

The porosity of our soils mean that they act like a sponge, absorbing the rainfall that comes in the winter and spring months and holding it for the vines to access during the growing season. We've done backhoe cuts in late summer, after it hasn't rained for several months, and while the top few feet of soil are dry, there's moisture in the layers six feet down and more.

At the same time, we never see water pooling around the vines. Part of that is that our whole property is hilly. But hillside vineyards in other regions still end up with standing water at the bottoms of the hills. We never do. That balance of water retention and drainage is ideal, and it allows us to dry-farm in the summer months of what is essentially a desert climate. 

Benefit 2: Higher Acids at Harvest
We've had anecdotal evidence of calcium-rich soils producing wines with more freshness for years. At the symposium on Roussanne that we conducted last decade, producers from non-calcareous regions (from Napa to the Sierra Foothills to vineyards in eastern Paso Robles with alluvial soils) consistently reported harvesting Roussanne roughly half a pH point higher than those of us from calcareous regions like west Paso Robles and the Santa Ynez Valley. But the chemistry of why this was the case has only become clear in recent years. 

It appears that the key nutrient here is potassium, which is central to the processes by which grapevines lower acidity in berries as fruit ripens. High calcium levels displace potassium in the soils, inhibiting this chemical process and leaving more acidity at any given sugar level. Of course, this can be a challenge. I have friends in other parts of Paso Robles whose pH readings are so low at the sugar levels that we like to pick at (say, 22-24° Brix) that they have no choice but to wait for higher sugars. This can produce wines that carry massive levels of alcohol. But in moderation, it's a wonderful thing. I'm grateful that (unlike in many California regions) we can let malolactic fermentation proceed naturally, producing a creamy mouthfeel without unpleasantly high alcohol levels. In much of California, the higher harvest pH readings mean that they have no choice but to stop the malolactic bacteria from working to preserve the sharper malic acids in the finished wines, for balance. 

The calcium-rich layers of the mountain behind the winery shine bright white in mid-summer

Benefit 3: Root System and Vine Development
Unlike cereals and other annual crops that have shallow root systems, grape vines have deep root systems. This means that the composition of the deeper soil layers is more important for vine health and wine character than that of the topsoil. It also means that amending the soil (by, for example, liming to add calcium) is less effective than is natural replenishment of essential nutrients from deeper layers. 

Grapevine roots are remarkable. They can penetrate dozens of feet into soil in their search for water and nutrients, and they continue to grow throughout the vines' lives. This means that the physical properties of the soil are important: a hardpan layer through which roots cannot penetrate can have a serious negative impact on a vine's output. Calcareous clay's tendency toward flocculation (soil particle aggregation) creates spaces in which water can be stored. In addition, the softness of these soils means that as they dry out, they shrink, creating fissures through which roots penetrate to where more residual moisture can be found. As they get wet, they expand again, opening up yet more terrain for the vines' roots to access. This process repeats itself annually. In our vineyard we've routinely found grapevine roots ten feet deep and deeper in experimental excavations.

Benefit 4: Disease Resistance
Finally, there is evidence that calcium is essential for the formation of disease-resistant berries. Calcium is found in berries in its greatest concentration in the skins, and essential for the creation of strong cell walls and maintaining skin cohesion. However, if calcium is scarce, plants prioritize intracellular calcium over berry skin calcium and berries are more susceptible to enzyme attack and fungal diseases.

Where Are California's Calcareous Soils?
When my dad and the Perrin brothers were looking for a place to found the winery that would become Tablas Creek, calcareous soils were one of three main criteria they were looking to satisfy (the others were sun/heat/cooling and rainfall). But they quickly realized that soils like these are rare in California, except in a crescent of land in the Central Coast between the Santa Cruz Mountains to the north and Lompoc to the south. The portion of this this area that is on the western slope of the coastal mountain ranges is too cold to ripen most Rhone varieties. The western and southern pieces of the Paso Robles AVA, on the eastern slopes of the Santa Lucia Mountains, are home to the state's largest exposed calcareous layers, and it's largely because of this that in 1989 we bought property here.

There's a great story about how they went about finding soils. As they tell it, they decided that it was a lot cheaper and faster to look at road cuts than to hire backhoes and dig their own. They looked for the better part of four years around California without finding soils that excited them. Until they were driving along Peachy Canyon Road one afternoon in 1989, saw one of the many switchbacks where CalTrans had dug into the hillside to make the roadbed, and pulled over to see if the white rocks that they noticed were really what they'd been searching for. The composition looked right, the fossils looked right, and they then brought over a French geologist to confirm their impressions. They put in an offer on the property where we are now later that year.

We've thought since the beginning that finding calcareous soils would be a key to making great wines. Learning the science behind why only underscores the importance that the vineyard's founders put on this search.

Further Reading:
Thanks to Dr. Thomas J. Rice, Professor Emeritus of Soil Science at Cal Poly, for pointing me in the right direction on some of the trickier geology questions. See also:

• "Calcium in Viticulture: Unraveling the Mystique of French Terroir, Part I and Part II" by Valerie Sexton, Wine Business Monthly. Originally published September/October 2002.
• "Effects of juice pH and potassium on juice and wine quality, and regulation of potassium in grapevines through rootstocks (Vitis): a short review," by S. Kodur, Department of Agricultural Sciences, La Trobe University, Bundoora, Victoria, Australia, 2011.
• "Effect of rootstock on must and wine composition and the sensory properties of Cabernet Sauvignon grown at Langhorne Creek, South Australia," by R. Gawel, A. Ewart and R. Cirami. Wine & Viticulture Journal, January 2000.

A Summer Solstice Vineyard Walking Tour

For the last three months, I've been taking walks through the vineyard every Wednesday morning to gather photographs to share during the weekly Instagram Live broadcasts I've been hosting from Tablas Creek. This has given me a more consistent archive of the changes in the vineyard landscape than I've ever had before. And even as we've reopened our tasting room this week (hooray!) I'm going to continue these weekly walks and reports, to make sure that we can share what's going on here with everyone, whether or not they're able or comfortable to come for a visit.

The landscape has made its annual transformation from late winter shaggy green, with soft edges around dormant vines, to midsummer vibrancy, with golden hillsides, brown earth, and intensely green vines. After months of transition, the last two weeks have felt complete. Here's a visual tour. First, to set the stage, a long view looking down from the vineyard's highest spot, through Grenache vines and over Counoise, Tannat, and to a block (on the far hill) that used to be Grenache Blanc and is now home to our newest grape, Muscardin:

A photo from within that new Muscardin block shows what it looks like, two weeks post-grafting (left). A close-up of one of the grafts (right) shows the new Muscardin bud already sprouting. 

The twelve additional (short) rows that we grafted over to Muscardin will more than double what we put into the vineyard last year, and will give us enough to really wrap our heads around it when it gets into production next year. If you're interested in learning a little more about this exceptionally rare grape, I summarized the little that's available in the literature in a post last summer.

The vineyard, after a longer-than-normal period of shagginess due to the late rain we received and our caution in trying to minimize staff out here in the early days of the Covid-19 shutdown, is mostly back looking tidy. Here are two views. On the left,  down through a Mourvedre block toward Las Tablas Creek, and on the right, a view through our old Vermentino block. Click on either for a larger view:

We've seen an excellent fruit set this year, with virtually no shatter and uniform, healthy clusters. Below, see Vermentino (left) and Grenache (right), two of our earlier varieties, whose berries are already pea-size or larger and mostly round:

But even less precocious grapes like Mourvedre (left) and Syrah (right) have made good progress too. If I had to make a prediction, it would be that we're looking at veraison and harvest more or less on schedule with the past two year, at times close to our 20-year averages:

The next photo, of a head-trained Tannat block in the middle of the vineyard, shows why it's so important for us to get in and clean out the weeds in these blocks early in the growing season. Already, the vines are bushy enough that their canes almost touch, and running a tractor through here would damage the vines.

In the trellised sections of the vineyard (like the Counoise block below) we've been finishing up our shoot thinning. This process helps open up the canopies to the free flow of light and air, and allows us to reduce and even the crop load from vine to vine to encourage even ripening. You can see the canes that we've discarded on the ground:

Although we're still two months or more away from harvesting any grapes, many of the fruit trees that we have interplanted in the vineyard are getting closer to their own harvests. We've been enjoying cherries the last couple of weeks, and this apple (pictured in front of a head-trained Mourvedre block) is set with a heavy crop and looking like we'll start to get fruit in July.  

I'll leave you with one last photo, of one of our handsome Grenache vines from our original plantings in 1992. At nearly three decades old, it's solidly in its prime, but looks like it's got decades of high quality production ahead of it. 

So, that's the report from the vineyard, as of mid-June. Looking great. Full speed ahead.

Flowering 2020: A little delayed, but all the more welcome

Budbreak gave us the first sign that we were on at least a somewhat later track this year. Flowering, which I've been waiting to see for a couple of weeks now, confirms it. This suggests that we're looking at a similarly cool beginning of the growing season to what we saw in 2018 and 2019 (and different from the warmer, earlier beginnings of 2013-2017). Please join me in welcoming the first flowers of the year, a Viognier vine courtesy of Viticulturist Jordan Lonborg:

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. As with all parts of the vineyard annual cycle, there are grapes that enter (and exit) flowering earlier and later, with the early grapes being Viognier, Grenache, Grenache Blanc, and Vermentino. They are followed shortly by Marsanne and Syrah, and finally, as much as a month after the early grapes, Roussanne, Counoise, and Mourvedre bring up the rear. Flowering is the second of the four 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 beginning late March or early April, and lasting three weeks or so)
• Flowering (typically beginning mid-May, lasting a month or so)
• Veraison (typically beginning late July or early August, lasting as much as 6 weeks)
• Harvest (typically beginning late August or early September, lasting two months or so)

You might notice that in the above list, the duration of each stage is longer than the previous one. That's because grapes start their growing cycle at different times, and also proceed at different rates. So, harvest stretches over a longer time than veraison, which takes longer than flowering, which takes longer than budbreak. Given that today was the first day we saw any flowering, we're likely to be enjoying grape bloom until the second half of June.

During flowering, you hope for consistent, sunny weather, with only limited wind and no rain. So, the two-tenths of an inch of rain we got overnight, and the wind that we're getting today, aren't ideal. 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. Still, we're so early in flowering, with only Viognier showing any blooms, that what really matters is what the weather is like for the next month.

How close are the other grapes to flowering? It depends. A grape like Grenache Blanc looks like it may be a week away, or less:

Whereas with later grapes like Roussanne, Counoise or Mourvedre (below), the flower clusters are just forming, and likely won't bloom for the better part of a month:

I'll leave you with one more photo of the newly blooming Viognier. It may not look like much, but it's an important milestone nonetheless. Full speed ahead. 

A last look back at the winter of 2019-20

This week, it finally feels like we've made the pivot from spring to summer. After several weeks of cool, wet weather, which delayed the spread of budbreak and encouraged an explosion of cover crop growth, this week it's sunny and warm. It's hit 82, 87, and 90 the last three days, quadrupling our total number of 80+ days in 2020. We're supposed to see another week or more of temperatures in the mid-to-upper 80s, and there's no rain on the horizon.

With that backdrop, I thought it would be a good time to look back on our most recent winter and see how it compares to other recent years. First, a look at rainfall by month:

You can see our late beginning to the rainy season (that November rainfall didn't start until the 26th), the wet December, a record-dry January and February, and the relatively wet last two months. Overall, with only limited prospects for additional precipitation, we're at 16.97" of rain for the winter, 71% of our 24-year average. That's lower than we'd like to see, of course, but with a wet winter last year, it's OK, and better than 10 of those 24 years:

In terms of temperature, we saw 30 below-freezing nights, with our first at the end of October and our last just two weeks ago, on April 7th. Over the last decade, we've averaged 34.5 below-freezing nights, so overall, this year was pretty normal. (If you're curious, our frostiest recent winter was 2011-12, with 57 below-freezing nights, and our least frosty was 2014-15, with just 13.) Our frostiest month was January, which, as you can see below, isn't always the case. Many years, it's too wet in January for it to drop below freezing. Compared to the rest of the last decade:

My sense that March and April were cooler than normal is reflected in the graph above, as well as in the fact that our average high temperatures in March (59.8°F) and April (65.5°F) were colder than the average highs in January (60°F) and February (68.3°F). I don't remember ever seeing that before!

The net result is a vineyard that's in excellent shape to attack the growing season with vigor. The cover crops are lush and deep, and Nathan is starting to cut and bale the sections that the flock couldn't get into in the last six or so weeks. You can see the height of the cover crops dramatically in the vineyard blocks where we've mowed every-other row, to give better air drainage and protect the new growth from frost:

So far, we've seen zero frost damage even from our couple of early-April below-freezing nights, as they affected only the lowest-lying areas, none of which had yet sprouted. The below Grenache block is in one of those lower areas, and it is healthy, vigorous, and doing its best to make up for lost time:  

This is one of my favorite times of year in the vineyard. Everything is still green, new growth is exploding out of the gnarled vine trunks, and the vineyard's patterns are starting to come into focus as we begin the long process of turning the cover crops under so they can decompose and provide nutrients to the vines' roots. It's going to be an even longer process than usual this year. The section in the valley in the below photo is Tannat that we turned under in late February, hoping to get a jump on the weeding process. It's already regrown. 

For scale, here's me in the Pinot Noir vineyard at my mom's house that is the source of the Tablas Creek Full Circle Pinot Noir. Not pictured: Sadie, who like the vines isn't tall enough to be visible in the high grass:

Overall, it's hard not to be optimistic. Wildflowers are everywhere, and the vineyard looks healthy and beautiful as we begin turning the cover crops under. If it's a little shaggier than normal for late April, well, it's not alone. We're all a bit overdue for a haircut.

Budbreak 2020: The World May Be Crazy, but the Vineyard is Right on Time

This winter has very much been one of phases. November was chilly but almost entirely dry, which got us into dormancy early but put us a bit behind in cover crop growth. December was very wet, with 6.66 inches of rain and 13 days with measurable precipitation. January and February stayed chilly (18 below-freezing nights) but saw very little precipitation. The sun and the saturated soil from our wet December produced a vineyard that grew greener by the day, but since wet soils hold temperature better than dry ones, raised the specter of very early bud break if we didn't get more rain soon. But then March turned wet and remained cold, dropping soil temperatures and keeping the vineyard in stasis for longer than I thought possible. The rainfall-by-month graph for the winter so far shows the whipsaw nature of what we've seen:

The vineyard's long period of dormancy is ending. The proliferation of California poppies are an indicator that the lengthening days and the warm sun will begin to wake up the vines:

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, Grenache, and Vermentino tend to go first, followed by Syrah, Marsanne, Tannat, and Picpoul, and finally, often three weeks or more after the earliest grapes sprouted, Roussanne, Counoise, and Mourvedre. And it really is just starting. We only have budbreak in Viognier, the two Grenaches, and (bizarrely) the very top of one Mourvedre block. The below photo is Grenache:

This year is later than many years last decade, and a month later than our record-early 2016, but it's only about average for what we'd have expected historically. When we saw first budbreak the last dozen years gives a good overview:

2019: Late March
2018: Late March
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

It's important to note that the vast majority of the vineyard is still dormant. I was only able to find leaves in our earliest-sprouting grapes and only at the tops of the hills, which are warmer than the valleys, where cold air settles. And even where it's begun, with the exception of the earliest Grenache blocks, all there is to see is swollen buds like the one below, from the Haas Vineyard Pinot Noir:

It will be at least another few weeks before we see sprouting in late-emerging grapes like Counoise or Roussanne, or in low-lying areas. This Mourvedre block is one of many that show no signs of sprouting yet:

Why does budbreak happen when it does? It's mostly a question of soil temperatures. Grapevines (and all deciduous plants) are spurred by rising soil temperatures to come out of dormancy and begin their growing season. Evolutionarily, plants are trying to balance competing goals: to sprout early enough to achieve maximum carbohydrate generation from photosynthesis (i.e. ripen their fruit so animals eat it and distribute the seeds) while staying dormant long enough to avoid suffering damage to their reproductive prospects through frost.

Frost is on our minds. Before budbreak, the vines are safely dormant, and a freeze doesn't harm them. But once they sprout, the 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 I'm thankful that 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. 

You might think that earlier budbreaks increase your risks of frost. And yes, all other things being equal, having fewer nights where you have to worry about temperatures dropping below freezing is better than having more. But if you look at the two most recent frost years (2009 and 2011) both of those saw budbreak in April. Is it possible that the same conditions that keep a vineyard dormant longer in the spring raise the risks of frost damage once they finally do sprout? I think so. California weather patterns tend to be long-wave patterns, where conditions are more likely to be similar to what they are now in two weeks than to have changed entirely. That's unlike, say, Vermont, where I grew up, where it always seemed to me that each week's weather could just as easily have been generated by a random weather generator.

That said, looking at the long-term forecast offers some hope. We're supposed to get one more chilly late-winter storm next weekend, but it doesn't seem likely to be cold enough to damage the tops of our hills, and it doesn't seem like we will have progressed far enough for anything else to have sprouted. After that, we're expecting drier weather as the storm track shifts north. But there's a long way to go.

Meanwhile, we'll enjoy the rapid changes in the vineyard, and the hope that always comes with the emergence of new buds. Please join me in welcoming the 2020 vintage.

A Walk through the Vineyard, Poised between Winter and Spring

Even as we have implemented major changes to the business side of what we do, the vineyard continues its march through the seasons. The grapevines don't know that there's a shelter at home order. The cover crops aren't interested in quarantine details. Instead, they're paying attention to signals like soil temperature and hours of sun as their systems make the annual determination as to whether it's time to come out of dormancy yet.

We've finished the winter pruning work we needed to do, and we have six weeks or so before we're far enough into the growing season to need a large crew working on anything (the next big push will be shoot thinning). So, if we had to pick a time when it doesn't hurt us much to cut back on vineyard work and wait this out, this is a pretty good one.

I took a walk through the vineyard on Thursday to get a sense of where things were. After our nearly-entirely-dry January and February (just one storm, 1.11 inches total rainfall) it's clear that the rain we've received so far in March (4.16" across 13 different days) has made a significant difference. The ground is saturated. The cover crops have doubled in size. And the generally cool daytime temperatures (just 5 days this month that made it out of the low-60s, and only one in the last two weeks) and chilly nights (four have dropped below freezing) have delayed budbreak to a more-or-less normal time frame. Although it can't be long now, in my walk I didn't see anything that had pushed buds, even at the very tops of the hills and the very earliest varieties like Vermentino, Viognier, and Grenache Blanc.

What did I see? The wildflower season just beginning, with wild mustard the most precocious:

I took one shot (through our deer fence) of the sign pointing to our tasting room if you were to approach the vineyard on Adelaida Road from the north. If you are used to seeing Paso Robles in summertime when everything is golden and in sharp relief, the softer springtime contours can be surprising.

The dormant gray vines (Vermentino here) make for a great contrast this time of year with the green cover crop and the early wildflowers:

The day, like most of last week, saw a shower pass through. You can see the clouds hanging over the vineyard in this shot, looking down over our oldest Counoise block:

And finally, a shot looking up from more or less the middle of the vineyard over one of our Grenache blocks, a study in green, blue, and white:

If you'd like something more immersive than the still photos, I took a 20-second video in the middle of the vineyard too. I highly recommend turning on your volume.

Seems like most of us could use 20 seconds of spring vineyard breezes and birdsong right about now. Repeat as necessary. pic.twitter.com/EloZY8exiP

— Tablas Creek (@TablasCreek) March 20, 2020

Although we're not able to welcome you here in person right now, I'll look forward to sharing what the vineyard looks like more regularly over coming weeks. That way, you can follow along. And if there are things you particularly want to see or know more about, please leave a comment. Meanwhile, stay safe out there.

The Vineyard After a Wet December and a Sunny January is Impossibly Green

Last week, I commented on Twitter that we were entering the season where Paso Robles is absurdly beautiful everywhere you look. Don't believe me? Check it out for yourself.

December's rain and a mostly sunny January have combined to produce an explosion of cover crop growth, and everything is the intense yellow-green that winter in California produces, so different from the summer gold. There are clouds in the sky to provide contrast to the brilliant blues, the angle of the sun is lower, and you feel like you can hear the grasses growing, making the most of their brief time when moisture is readily available. This morning seemed like a good time to get out on a ramble through the vineyard to document how things look.

Our flock of sheep, if you visit this week, is hard to miss. They've been moving up the hillside behind the winery (which we call "Mount Mourvedre" because that's what's planted there), spending just a day or two in each long rectangular block before being moved up the hill to new (yes, greener) pastures. From just inside our front gate:

You may notice, looking past the solar panels, that there's a horizontal line a few rows below where the sheep are now. That's the boundary line between where the sheep were until this morning and the new section they just got into. We keep them in any one block no more than 48 hours, so they graze evenly but don't overgraze, and the grasses have a chance to regrow and build more organic matter this winter. Looking down the electric fence line makes it even clearer. The downhill section has been grazed already, while the flock is just getting started on the new uphill section they're in now:

The cover crop, in areas the sheep haven't gotten to yet, is a little behind where it often is at this time of year because of how late the rain first arrived. But it's making up for lost time quickly, and is about four inches think already. You can see it clearly in this shot, looking uphill through our oldest Grenache block toward some endposts that mark the beginning of a north-facing Marsanne section. When I walked up the hill, there was a turkey vulture on each post, every one basking in the morning sunshine:

Another view, focused on the vultures more than the green:

Turning around and looking down the hill, through the Grenache block and over the Counoise, Mourvedre, Tannat, Roussanne, and Grenache Blanc sections, gives you a sense of the patchwork of vineyard contours, as well as how green everything is. The more gray-green foliage of the olives stands out clearly.

While we needed this sunny January to get the cover crop growing and accumulating biomass, it has put us a bit behind where we'd hope we'd be in terms of rainfall. With the month almost over and no real signs of wet weather for the next couple of weeks, we're only at about 72% of normal rainfall to date. There's still plenty of winter to go, and plenty of moisture in the ground, but we're hoping for a wet February and March. For the winter so far:

Still, none of us are too worried. We've gotten enough rain to this point to have plenty of fodder for our sheep. There's lots more winter to come. And the sunsets? Those are a very nice reward.

I've said it before, but I'll say it again. If you haven't visited Paso Robles in the winter, you're missing out. We'll see you soon.

Six inches of rain in two weeks begins the vineyard's winter transformation

California, when it rains, is a paradise. The landscape transforms from stark browns and golds to something softer, with blurred edges. Green appears, seemingly overnight, as grasses and broadleaf seeds that have been waiting for moisture sprout and push leaves above the surface. Puffy white clouds appear in the sky, which has unbroken blue for months at a time in the summer. The images aren't the same as those that summertime visitors love, but for me, they're even better. I'll share a few of my favorites from a vineyard ramble this morning:

You can see that higher up in the vineyard, where this Counoise block is, we still have leaves on some of the vines. Although we've had several nights where our lower-lying areas have seen frost, we haven't had the hard freeze that will force the vineyard into dormancy top to bottom yet. This lower section is more representative. I particularly like the green that has already appeared:

The total lack of moisture in the summer has its own appeal, but the fog does give a better sense of distance, settling in the undulations of the hills:

The rain did us the favor of cleaning off our solar panels. Their modern regularity makes for a nice contrast with the sky and landscape:

The rain itself came in nearly ideal distribution. Up through November 25th we'd seen zero precipitation this winter. In the 13 days since, we've had measurable rainfall 12 of the 13. But it was generally modest. We only topped one inch once (1.47", on December 4th). Five other days saw between one-half and one inch. And very wet days tended to be followed by days with less rainfall, allowing everything to soak in:

So far, for the winter, we've totaled 5.88", which puts us at about 125% of normal at this point in the rainy season. Given where we were a month ago, that's pretty encouraging. It's also some validation to the research I did after that blog, which suggested that a dry beginning to the winter was only slightly correlated with a dry winter. 

What's next for us? A week, more or less, of sunny, dry weather. That's perfect, as it will give the new green cover crop a chance to get some growth in before the next rains come. After that, it's anyone's guess. Long-term predictions are still for a slightly drier than normal winter, but I feel a lot better about things given what we've banked already. As the mud on my boots suggests, there's plenty of moisture to work with, for now.

I'll leave you with my favorite photo of the morning, sun partially obscured by the fog, solar panels in the foreground, olive trees and vineyard truck in the middle ground, and vineyard sloping away down toward Las Tablas Creek in the background. The fog has since burned off, but I look forward to more moisture over the coming days.

A Dry, Chilly Beginning to the 2019 Winter Season

Those of you who have been following California's recurring struggles with fire won't be surprised to hear that it's been dry. Record low relative humidity has been a major contributing factor to the wildfires that have raged in both northern and southern California. Here in Paso Robles, we haven't seen the same high winds that fueled this year's terrible fire season, and one somewhat comforting fact is that those sorts of wind events are quite rare here, as the Santa Ana winds that affect southern California don't often make it this far north, while the Diablo winds that affect northern California don't typically make it this far south. Still, it's been really dry, with no rain yet, relative humidity dropping into the mid-single digits the last few days, and the lowest dew point I can ever remember seeing (-3°F) on Halloween. There have been several mornings over the last couple of weeks where I've gone out to my car in the morning, had it be below freezing, and yet have no frost on the windshield because it's just been too dry.

What may not be so obvious from the news coverage is that it's been quite cold so far as we've transitioned from fall to winter. We've already had several frost nights in our lower-lying spots, and the vines are mostly in dormancy. Check out the difference in the look of one of our old Roussanne blocks from a month ago:

To today:

And we haven't even been the coldest spot in Paso Robles. If you look at the Paso Robles Wine Country Alliance's weather summary for October 31st (the day with the amazingly low dew point) you can see that there were several local weather stations that measured lows around 20°F and one that even dropped into the teens. And yes, even on this day with some very cold mornings, we had warm afternoons. The diurnal temperature swings, always big here in Paso Robles, reach extreme (50+°F) levels during this season:

Even with the cold nights, the hilltops are still showing nice fall colors, and are likely to until we see a hard freeze. This photo, of one of our Syrah blocks, is just up the hill from the Roussanne block I photographed above:

How unusual is all this, and what does it mean for our prospects for a wet winter? Not particularly, and not much. We see our first rainfall of the winter by the end of October about three-quarters of the time. The rest of the years, which have included 1996, 1999, 2003, 2005, and 2017, it's been dry into November. A lack of early rainfall has not particularly impacted what the rest of the winter has looked like; those five years have averaged 22.5 inches of winter rainfall, only about an inch and a half different from the 24.2 inch 20-year average. As the 1.5 inch difference is exactly what we've averaged in our last twenty Octobers, there's essentially no correlation between a dry October and a dry winter. That's a reassuring thought.

While we'd like it wet, the cold is a good thing, as it forces the vines into dormancy and keeps them from expending extra energy at a time of year when there's no fruit to ripen. And we'll take what we can get, while we wait for the long-term forecast to show some hope for rain. We'd like to get our cover crop growing, so our sheep have something to eat. And rain would put to bed any lingering worries about this year's wildfire season. There no rain forecast for the next two weeks: more dry weather, with sunny, warm days in the upper 70s and low 80s, with chilly nights dropping to around freezing. But while our vines would like to usher in the rainy season, that sounds like pretty ideal weather for people. If you're coming to Paso Robles between now and Thanksgiving, it sounds like you can expect conditions to be pretty great.

Meanwhile, we'll look forward to the greens, yellows, and oranges of the harvest season transitioning to the softer browns of fall, like the Mourvedre block below. It may not have autumn's drama, but it's beautiful in its own right.

Harvest 2019 Recap: What's Usually a Marathon Turns Out to Be a Sprint

Last Wednesday, as I was on the road heading to the (remarkable) New York Wine Experience, the cellar team brought in the last lot of grapes from the 2019 harvest, some head-trained Counoise from our Scruffy Hill block. This capped a 40-day sprint: our shortest harvest in 18 years, and longer only in our history than the tiny frost-reduced crop of 2001. That 40 days is a full two weeks shorter than our average this millennium. But unlike in some of the other attenuated harvests, we didn't have to pick because there was a threat of imminent rain, or heat. No, it was just that the consistently warm, sunny weather that we've seen since early August meant that everything was ready. No wonder our cellar crew was ready to celebrate:

Because the weather never forced us to pause, the breakdown of our workflow was nearly constant. After a slow start the last week of August and first two weeks of September (after which we sat at only 10% complete) starting September 16th we picked nearly every day until the end of harvest. You can see steadiness of the vintage in the chart below (in the chart, blue is purchased fruit for the Patelin program, and orange estate-grown fruit):

Yields defy an easy explanation. We ended up down overall about 8% from 2018, but while overall we were almost exactly at our long-time average, the picture depends a lot on which grape you look at. I'll dive into that below. But what stood out to me was that although we had great rainfall last winter, and exceptional vine health all summer, we didn't see the high yields that typically come with that. The complete picture:

Grape	2019 Yields (tons)	2018 Yields (tons)	% Change vs. 2018
Viognier	17.4	18.2	-4.4%
Marsanne	12.3	11.8	+4.2%
Grenache Blanc	28.3	43.6	-35.1%
Picpoul Blanc	8.6	9.1	-5.5%
Vermentino	24.7	17.9	+38.0%
Roussanne	46.1	32.6	+41.4%
Other whites	7.8	6.1	+27.9%
Total Whites	145.2	139.3	+4.2%
Grenache	51.4	74.3	-30.8%
Syrah	42.5	44.7	-4.9%
Mourvedre	49.6	64.4	-23.0%
Tannat	19.0	19.8	-4.0%
Counoise	20.0	16.0	+25.0%
Other reds	5.6	3.8	+47.4%
Total Reds	188.1	223.0	-15.7%
Total	333.3	362.3	-8.0%

Average yields ended up at 3.02 tons per acre, nearly exactly at our ten-year average. Other years right around 3 tons per acre read like a litany of our favorite-ever vintages: 2003, 2007, 2014, and 2016. As to why we saw only average yields despite the ample rainfall that we saw last winter, I blame a handful of small things: we saw some shatter in our Grenache blocks due to cool weather at flowering; we decided that we'd been hanging too much crop on our Grenache Blanc and were more aggressive in thinning, and (the only one of these which is troubling) Mourvedre, which didn't suffer from shatter, still hung a small crop. We'll be spending some time in the slower season to come trying to come up with a program to reverse this development, as we've done successfully in recent years with Roussanne. Speaking of Roussanne, it's clear from the increased Roussanne crop that the health that we noticed all growing season in our Roussanne was reflected in the quantity we harvested. It was also reflected in the fact that we didn't need to make nearly as many passes through our Roussanne blocks. It's the first time in a while that we've had extra lines on our harvest chalkboard, as we picked 95 lots this year (20 fewer than 2018). And that's including our first-ever picks of Bourboulenc, Cinsaut, and Vaccarese, noted in all-caps and with extra stars on the board:

Another way that you can get a quick assessment of concentration is to look at average sugars and acids. Since 2007, the average degrees Brix and pH:

Year	Avg. Sugars	Avg. pH
2007	24.42	3.67
2008	23.87	3.64
2009	23.42	3.69
2010	22.68	3.51
2011	22.39	3.50
2012	22.83	3.65
2013	22.90	3.63
2014	23.18	3.59
2015	22.60	3.59
2016	22.04	3.71
2017	22.87	3.74
2018	22.80	3.62
2019	22.30	3.62

You'll note that 2019's sugars saw a small decline from the past two years while the average pH maintained the level we were very happy with last year. The main culprit on the lower harvest sugars were Marsanne and Roussanne, both of which came in, on average, below 20° Brix. That's not a problem with Marsanne -- we typically love it around 12% alcohol -- but it suggests that we'll have a range of Roussannes, including those riper lots that are more likely to be appropriate for Esprit Blanc, and those that may be better suited for the Cotes Blanc or Patelin Blanc. I wouldn't be surprised to see both those wines with a higher than normal percentage of Roussanne in 2019.

The continued lower average pH is a great sign of the health of the vines, and the relative lack of stress that the vineyard was under at harvest time.

I had a sense, from living here and evaluating what I felt week by week, that we were really looking at two distinct weather patterns: a fairly cool one that lasted until the end of July, and then a consistent, warm pattern that took over in early August and lasted until mid-October. And the degree days that we measured this 2019 growing season support that, more or less. The chart below shows the unusually chilly May, the moderate June and July, and then the warmer-than-n0rmal (but not scorching) August and September. Note that October's information is for the first 16 days, as we picked our last block on October 16th:

I mentioned in my introduction that the duration of harvest -- 40 days -- was our shortest since 2001. That's noteworthy enough. But just as unusual was the sequencing of the different grapes. The cool weather in May seems to have set back the early grapes somewhat. Viognier -- which started coming in September 7th -- and Vermentino, Syrah, and Grenache Blanc -- all of which saw their first estate picks September 16th -- were delayed about two weeks compared to our average this decade. This delay in our early grapes led me to conclude mistakenly that we were looking at a later-than-normal harvest. But the late grapes, which flower in June and do the bulk of their ripening in the August-September period where we saw ideal conditions, were actually picked early. We saw our first picks of Roussanne on September 6th and Counoise on September 12th, both three weeks or so before we'd normally expect them. Grenache Noir, which usually lags behind Syrah by a couple of weeks, came in right on its heels, just one day later this year. And we were totally done with Roussanne by October 7th, which is really unusual.

In character, it's early to tell what things will be like, but so far, we're excited. I asked Winemaker Neil Collins to sum up the vintage based on what he's seen so far, and his response was, "the ferments have been wonderfully slow and measured. It is early for me to say just what to expect from the wines themselves but the whites seem aromatic and quite showy, pretty and delicate wines. Reds have nice rich color and are solid in structure while yet being quite plush and rich in texture." Senior Assistant Winemaker Chelsea Franchi added that it's "a vintage marked by balance." We'll know more, of course, in coming weeks.

Of course, just because we've finished picking doesn't mean that we're done with our cellar work. There are still plenty of lots to be pressed off, tanks to be dug out, and fermentations to monitor. But it feels different than it does earlier in harvest, when you're emptying tanks to make room for the next pick. Now, when we press something off and clean a tank out, that's the last time of the season. We've already put a couple of our open-top fermenters outside, where they'll winter over without taking up space. And the late-season sun shining through the presses make the afternoon warmth that much sweeter: 

Now that the fruit is in, it's welcome to start raining any time (although, to be fair, it doesn't look like there's any precipitation in the long-term forecast). Meanwhile, we're putting the vineyard to bed, seeding cover crop, and getting the animals back into the vineyard, to clean up any second crop clusters still on the vines and start spreading manure in preparation for the rainy season. Even in years like this when there's no inclement weather during harvest, it's still a relief when everything is in tanks and barrels, and you just don't have to worry about rain, or frost, or anything else. Whenever winter feels like coming, we'll be ready. And that's something to celebrate, in and of itself.