2015 International Grenache Day - The Cellar Crew Harvests Grenache

By Lauren Phelps

Today is International Grenache Day and enthusiasts are connecting all over the world and coming together to celebrate this unique grape. (For a fun overview, check out the #GrenacheDay hashtag on Twitter.) We celebrated by harvesting a half-acre block of our vineyard that was originally planted by our VINsider Wine Club members back in 2003.  The hands-on seminar focused on planting and vineyard care and gave members an opportunity to make an impact on the vineyard and wine we’re working with today.

Early this morning, Viticulturist Levi Glenn and his trusty vineyard dog Mavis collected samples from the block we call Grenache Noir Wine Club Head Pruned -- GNWCHP for short -- to test whether the lot was ready to pick.

Mavis Samples

Mavis is convinced; let's see what Neil Collins, Vineyard Manager and Executive Winemaker has to say.

Neil Sample

Neil used a refractometer to asses the sugar levels on the Grenache sample and decided we could harvest this block of estate Grenache.

Group Pick

Our cellar crew enjoyed a welcomed break from processing fruit and got to feel the sun on their faces as they picked Grenache in the vineyard this morning.

Grenache

The fruit looked spectacular and although yields looked light on this block, quality is fantastic!

Grapes with Hammer

We picked .75 tons from the head-pruned, dry-farmed lot.

Chelsea forklift

What a way to celebrate #Harvest2015 and International #GrenacheDay!  Cheers!


Mid-September Harvest Update: Why harvest started earlier than we predicted... and why our frighteningly low early yields may soon improve

Harvest, pushed by the last week of hot weather, has started to move fast.  We've brought in nearly 80% of the grapes for our Patelin de Tablas wines, and nearly finished our early white grapes (Viognier, Vermentino, Marsanne) here off the estate.  Tuesday, we picked our first estate reds, with two lots of Syrah. The harvest board is growing:

Harvest board 9.11.15

You'll notice that most of the entries on the board are in purple chalk, indicating that they're from purchased fruit. This reflects that most of the vineyards that we buy from for the Patelin wines are ahead of our own estate.  It's also a reflection that the grapes on which we base our Patelin wines (Grenache/Viognier for the white, and Syrah/Grenache for the red) ripen at the earlier end of the spectrum, while our two most important grapes for our estate wines (Roussanne and Mourvedre) ripen late.

Why harvest began earlier than we'd predicted
In my veraison post and harvest preview,  I predicted an early September start to harvest based on our date of first veraison and the range of times in recent years between veraison and harvest.  (The exact range I'd predicted was between August 28th and September 7th.)  Instead, we began picking Viognier off our estate on August 26th. Why? First, August was the warmest on record in San Luis Obispo County. Second, our VIognier harvest was exceptionally light.  Off of 5.8 producing acres, we harvested just 5.5 tons, less than half of last year's pig-reduced crop.  The tiny yields weren't unexpected, but they are unprecedented, and it's unsurprising that the combination of low yields and hot weather resulted in our shortest-ever time between veraison and harvest.

Our only other estate grape to come in in August was Vermentino, which had its own yield issues.  We've only picked one block (our cross-hairs, or CH block) but that block, which produced nearly 10 tons last year, yielded just 3.71 tons this year.  If not for these two low-yield-accelerated blocks, my prediction for an early-September start to harvest would look better.

Ongoing concerns on yields
We've known since our first Patelin lots of Viognier arrived that the grape was going to be scant, due to the third year of drought and cool, wet weather when it was flowering. Vermentino, though, was a bit of a surprise, and when it came in so light, it started a mild panic in the cellar.  We do have two other (smaller) blocks of Vermentino still to be picked, but it's now an open question as to whether or not we'll have enough even to supply a wine club shipment for 2015.

And yet, some things look fine
There are a few elements that are allowing us a glimmer of hope despite the painfully low yields on the grapes we've mostly picked.  

First is that the cold, unsettled May that we believe impacted the yields of the early-flowering grapes does not appear to have had the same impact on the later grapes like Roussanne, Mourvedre, and Counoise.  These June-flowering grapes look, from our vineyard surveys and our cluster counts, to be more or less in line with last year's yields.

Second is that the head-trained, dry-farmed blocks look fine.  I was out on Scruffy Hill yesterday, which is all head-trained and dry-farmed, and the yields looked quite healthy, both in Grenache (below, left) and Mourvedre (below, right):

Scruffy Grenache

Scruffy Mourvedre

 

Third, quality looks super. It's easier to tell at this stage on the reds, where you can look at thickness of skins and depth of color, and the first estate reds we've gotten have been dark, chewy, and flavorful. The initial bins of Syrah off the estate, below, show it well:

Syrah in bin

Fourth, there are some Patelin vineyards whose yields have been fine, with excellent quality.  Take, for example, the Estrella Syrah that came in on 8/21 and 8/22.  We'd been hoping for 25 tons, to form the chunky, meaty core of the Patelin red. The vineyard was productive enough that they were able to get us 31 tons.  This has helped us mitigate the fact that many other vineyards are seeing lower (and often dramatically lower) yields.  This Syrah, in the press, looks and smells great:

Syrah in press

Looking forward
The next few weeks will give us a much clearer sense of what 2015 will look like on our own vineyard. We're picking Grenache today, and it looks like we'll have a steady stream of estate lots (Syrah, Grenache, Grenache Blanc, our first Roussanne, and maybe even a little Mourvedre) coming in shortly. Stay tuned.


Harvest 2015 update: just over 15% completed & yields are looking low

By: Lauren Phelps

In the cellar, things are in full-gear!

Sorting Tablas_Cube

According to veteran Assistant Winemaker Chelsea Franchi harvest is already over 15% completed.  As of August 29th, we have worked with 65.82 tons of fruit.

Upright with Syrah_cube

The 1700 gallon French oak upright fermenters are all full fermenting Syrah for the 2015 Patelin de Tablas!

Harvest Sign First Estate_cube

Our first estate grapes were harvested on August 26th when we brought in about 3 tons of Viognier.  According to Viticulturist Levi Glenn, the estate Viognier yields appear down at least 50% due to the drought however, both acids and PH look great.

Mavis_cube

Levi's dog Mavis, vineyard dog extraordinaire, conducts a rigorous "lab test" of a bin of Viognier.

Although estate Viognier yields look low, Levi explains that "it's really more of a mixed bag.  Mourvedre and Roussanne both look a bit higher than normal".  In general, we're thrilled with the quality of fruit and a bit concerned since yields remind us of frost reduced years in 2001, 2009 and 2011.  We're waiting until we've harvested more from the estate to draw any firm conclusions.


Harvest 2015 begins and sounds alarm bells about yields

Today we welcomed into the cellar the first fruit of 2015: eight bins of Viognier from Fralich Vineyard, for our Patelin de Tablas Blanc.  And with that, the 2015 harvest is underway:

IMG_0657

IMG_0659

IMG_0645

Things look like they're moving pretty fast now, particularly after this past weekend saw temperatures soar into the low 100's both days.  It's cooled down since, but we're sampling most of the vineyards that we're expecting Syrah and Viognier from for Patelin and Patelin Blanc, and doing a first systematic pass through the same varieties in our own vineyard.  We'll get a little more fruit in tomorrow, then take a break to bottle the 2013 Esprit de Tablas before getting back at it next week.

It is wonderful to have the smell of new fruit in the cellar, particularly Viognier, which is as aromatic when it's newly picked as it is in the glass: honey and peaches and spice. And the fruit looked good.  But we were expecting something more like 15 bins today than the 8 we received. 

We expected that crop levels would be light in this fourth year of drought, and we know that some of the earlier grapes (notably Syrah and Viognier) were flowering during our unusually cool, breezy May.  These aren't ideal flowering conditions, and we've seen evidence of shatter in our own vineyard and from our expeditions to the vineyards we source from for Patelin.  But we were all taken by surprise by just how light this first pick turned out to be.

It is something of a maxim in vineyard analysis that when you see evidence of yields being light, they end up even lighter than you were thinking, while when you see evidence of heavier yields it ends up being even heavier than you expect.  And we have been seeing other evidence that yields will be light, from observations of lower cluster counts and smaller clusters to relatively high sugars and relatively high acids in our samples.  Perhaps less intuitively, further evidence is provided by the fact that the vines look notably healthy, when with heavier yields you would expect to see more signs of stress. 

So, I've been steeling myself for this news.  And with the Patelin, we have options; we have handshake agreements with several local vineyards that if we realize that we're light during harvest, they'll find some fruit for us.  We may not be able to make up all the difference, but we can bridge the gap a bit.  Those phone calls started this morning.

The estate vineyard, however, doesn't offer this recourse.  If we end up light, we just make less wine.  It's likely only another week before we find out the extent to which that will be true.

First day of harvest 2015 sign edited


Veraison 2015 Suggests an Early September Start to Harvest

Although we've been distracted by the more unusual occurrence of last weekend's summer rainstorm, this week also has provided the annual milestone of veraison.  Veraison marks the point where the grapes stop accumulating mass and start accumulating sugar (and, more noticeably, change color from green to red). It is one of the landmarks of the season, not least because it marks a point roughly six-weeks before the onset of harvest. As usual, we saw veraison first in Syrah, closely followed by Grenache and Mourvedre.  A few of the more colored Syrah clusters are below (though it's worth noting that even in these, there are still as many green berries as red, and that most of the clusters in the vineyard are still totally green):

Veraison 2015 syrah

While we expect to start our red harvest with Syrah sometime in early September, Mourvedre is an outlier, with relatively early veraison but an unusually long time between veraison and harvest.  Although we're starting to see color in many of our Mourvedre blocks, we don't expect it to come in before October:

Veraison 2015 mourvedre 2

I had to go to the very top of our Grenache blocks to find any color, and even there it's still just beginning.  We expect this to start coming in sometime in mid- to late-September:

Veraison 2015 grenache

The transformation between hard, sour green berries and sweet, soft, red berries takes some time, and when it starts depends both on how early the vine sprouts and begins to grow (determined largely by the date of the last winter freeze) and on how fast it can photosynthesize (determined by the amount of heat and sun after budbreak).  Some years (last year, for example, which was warm and frost-free) it was easy to know that we'd see an early veraison; the question was just how early.  When you have a year, like this year, that is giving contrasting conditions (a budbreak two weeks earlier than normal, followed by a summer that has alternated hot and cold and is currently 5% behind normal in heat accumulation) it's less obvious, and we watch for veraison's signs more eagerly.  You can see from the chart below, from the Western Weather Group's Paso Robles Wine Country Alliance forecast, where 2015 sits in degree days compared to other recent vintages:

Growing Degree Days 2015 edited

The duration between veraison and harvest is not totally constant, and is determined by the weather that we get in the interim.  The chart below shows the two dates for our last eight harvests, with the year linked to my blog post about veraison that year:

YearFirst Veraison NotedHarvest 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 20 ? ?

July 20th forms the median of the data points above, and suggests a beginning of harvest also sometime near normal.  Based on the range of days that it's taken between first veraison and harvest (between 39 and 49 days) that suggests that harvest will begin sometime between August 28th and September 7th.  Given that our crop levels are relatively light this year, I'm betting that it will be toward the early end of that range.

It is noteworthy, I think, that we've recovered from a two-weeks-earlier-than-normal budbreak to a normal veraison.  That we've already achieved two extra weeks on the vine compared to an average year is a good thing, given that the longer that the grapes can stay in contact with the vines, the more opportunity they have to pull character and minerality out of the soil.

Now, we start waiting, but at least we know roughly how much time is on the timer.


Did 2.6" of rain in July really just happen?

Yesterday, we hosted a seminar on dry-farming.  In the rain.  In Paso Robles.  In July.

Levi lecturing

And it wasn't just a little rain, either.  As we were talking about how we've been working to plant increasing acres of vines without any irrigation infrastructure, and how we've been weaning even our established vines off of needing regular water, we were in the process of accumulating more rain -- seven times more rain -- than Paso Robles had received in any July day in its history.  In fact, we received four times more rain yesterday than Paso Robles has ever received in an entire month of July before.

Of course, July is the driest month of the year in Paso Robles, averaging less than 0.2" of rain for the month.  But residents of other parts of the country may not realize just how unusual summer rain is in the Central Coast of California.  Maybe a graph will help (from the useful site climate-data.org):

Climate-graph-paso

The unusual storm was caused by the remnants of Hurricane Dolores, which instead of remaining offshore or moving inland toward Phoenix (both more common paths for Pacific ex-hurricanes) wandered slowly and more or less directly north up California's coast, bringing unusually hot, moisture-laden air to parts of the state where humidity is almost totally foreign.  This moist, unstable air spurred a series of thunderstorms (themselves rare in this area) whose path took them directly over Paso Robles.  The town recorded 3.55", the highest total in the county and more than a quarter of the average annual rainfall the city can expect to receive.  It's also more than the town averages in any month during the year; for those of you who like me need a translation from the metric, 3.55" is more or less 90mm... about 10% more than Paso Robles receives on average in January, its wettest month.  We saw a little less rain out here than they did in town, but at 2.6" we still received more than we did all but two months (December and February) this past winter.

Given how much rain we received, and how fast it came down, you might wonder how the vineyard fared. It came through with flying colors. We rarely see much erosion here, due to the porosity of the clay-limestone bedrock, and we didn't see any in the vineyard. The little we saw was confined to a few vineyard tracks, where the occasional tractor traffic compresses the soils enough that water runs down rather than soaking in. From this afternoon:

Minor erosion

We don't anticipate any serious negative consequences from the rain. After a last round of showers and thunderstorms that are forecast to blow through this evening, it's supposed to dry out. It looks like we'll have a few sunny, breezy, relatively cool, low humidity days, and then it will warm up to normal for the season (highs in the 90s and lows in the 50s, with virtually no humidity).  This should serve to dry out the surface layer of the soil, and prevent too many weed seeds from germinating.  Plus, both the low humidity and the warm days will serve to prevent mildew from becoming a problem.

On the positive side, this is a time of year when the vines are nearly all under some stress.  A dose of rain now helps alleviate this stress, and gives the vines the energy to make their final push toward ripeness.  And the amount of rain that we received was enough to get through the topsoil and replenish the moisture in at least the upper layers of the calcareous bedrock, which will provide a reservoir for the vines over the next couple of months.  You can see how rich and soft the soils look after the rain, and also how void of erosion channels they are even near the bottom of a steep hillside:

Brown dirt

If the rain had come a month later, with some grapes nearly ripe, we would worry that the water might dilute the flavors and even cause grapes to swell and split.  But now, with veraison barely started, that's not a risk.

It's worth remembering that most other wine regions, including the Rhone, see summer rain.  The same chart as above, for Chateauneuf-du-Pape, shows that while rain is a bit less common in the summer than in other seasons, it's hardly rare:

Avg rainfall CdP

So, we'll enjoy the unusual moisture in the air, and feel thankful that we got it now and not during harvest.  If this is a precursor to what is sounding likely to be a strong el nino winter, so much the better.  I'll leave you with one final photo, taken in the middle of yesterday's rain, and looking more like an impressionist painting than a summer Paso Robles landscape:

Mist and rain


State of the Vineyard, Mid-Summer Edition

This has been an unusual summer.  We had the warmest late-winter/early-spring anyone can remember. This was followed by the coolest May in 20 years. Then June was hot.  July, so far, has been cool, and we've even had (very unusual for summer in Paso Robles) a couple of showery days.

Overall, the year looks about average in terms of heat accumulation.  At 1276 degree days to date, we're about 10% behind where we've been the last three warm years (2012-2014 average on July 14th: 1483) but 15% ahead of the cool 2010 and 2011 vintages (average on July 14th: 1112).  Through it all, the vineyard continues to look remarkably healthy.  

To get a sense of how healthy, I'll start with this panoramic photo, taken this week, overlooking olur main Grenache block.  It's worth expanding it; click on it (or any photo) to see it bigger:

Panorama over Grenache

All this variation in the weather, particularly the warm April and the cold May, suggests that we'll see a harvest that will begin early and end late.  The grapes that had sprouted by early April (like Viognier, Grenache and Grenache Blanc) were spurred on by the warmth and sun, and pushed canes already a foot long or more by the time it cooled off in May.  The later-sprouting grapes (like Counoise, Mourvedre and Roussanne) were barely out when it got cold, and didn't really start growing until things warmed up again in June.  This led to a period in mid-June where the early varieties had grapes that were already pea-sized while many of the late varieties were still flowering.

Things have evened out in the last few weeks, but you can still see remnants of the uneven beginning in the different cluster and berry sizes.  First, Syrah, from near the top of the hill.  The berries look nearly full-sized, but we haven't seen any veraison yet:

Syrah clusters

Grenache, too, has grown a lot, though we do expect some added mass before they start to turn red:

Grenache clusters

Mourvedre is still farther away from being ready, with the grapes still as much oval as round, and small, hard and light green:

Mourvedre clusters

This same week last year, I was already talking about veraison in Syrah and Mourvedre.  2014's veraison was about 2 weeks earlier than normal, and this carried through to a mid-August beginning to harvest. The fact that we're still not seeing veraison suggests that we're likely looking at a later start to harvest than the last few years, and I'm also expecting a significantly later finish.  Could we start in late August and finish in early November?  It seems likely, at this point, though a stretch of hot (or cold) weather could move that around.

Crop levels seem down a bit compared to the past couple of years.  Given that we're now four years into our drought, that's hardly surprising.  But it doesn't look like it will be dramatically reduced, and the vineyard looks healthier than it has in mid-July in years.  Roussanne often is showing signs of stress by now, with leaves starting to yellow.  Not this year.  I'll leave you with one final shot of our Roussanne, sheltering under a vibrantly green canopy and beginning its long, slow trek toward what will likely be a mid-October harvest:

Through Roussanne row


Shatter explained: A perfect flower, but not a perfect bloom

By Levi Glenn

Every year there is a one- to two-week period when the vineyard smells wonderful. That's when you know bloom has arrived. It's not the unbelievably effusive smell of an orange grove in full blossom. Or the sweetly intoxicating blue bush lupine, a beautiful native wildflower we see each spring. The scent of a vineyard in full bloom is a bit more understated, elusive even. It's got a sweet floral note underscored by a deeper earthy character. The smell is fleeting, as is bloom. At least in most years.

Mourvedre in full bloom
A Mourvedre cluster in full bloom

Simply put, bloom is the window of time in which each individual flower pollinates itself. Grapevines have what is referred to as a perfect flower. Many crops require both male and female plants to produce fruit. A male flower's pollen is moved by wind (and often aided by honeybees) to help find its way to a female flower. Perfect flowers -- including grapes -- can self-pollinate. That is, unless something goes wrong. 

In our area, weather during bloom is typically optimal for even fruit set: warm, dry, not too much wind. 2015 has been a bit different. After a historically warm first four months and a correspondingly early emergence from dormancy, May was unseasonably cool. We had quite a bit of wind, and the fog produced by the onshore flow seemed relentless. There were even a couple light rain events. Wind can blow the pollen away, and rain or fog can make the flower cap stick. Both result in an unfertilized flower. With optimal conditions, bloom can be as fast as a week. This year, we have seen some blocks take close to a month to complete flowering. When a flower doesn't turn into a berry for whatever reason, we call that shatter (or coulure in french). When this is widespread over a vineyard, crop loss can be severe. The two examples below are the two ends of the spectrum.

 Full Grenache Cluster
A fully-fertilized Grenache cluster

Shattered Grenache ClusterA Grenache cluster with lots of shatter

Aborted BerriesUnfertilized Grenache berries

In addition to the Grenache -- which is known as a shatter-prone variety -- we have seen some shatter in Syrah.  But it's not even across the entire vineyard.  Grenache from warmer blocks that flowered first, during warm weather in late April, set quite well. Grenache from cooler, lower-lying parts of the vineyard that didn't get around to flowering until May show more shatter.  The Mourvedre and Roussanne that are finishing in our warm weather now don't show any signs of shatter. 

The conditions during bloom can dictate crop levels not only for this year, but also for next year. The 2016 inflorescence (cluster) is being formed right now whithin the bud located inside this years shoot. Growing conditions this year can affect how many clusters (typically one to three) will be inside next year's buds, and what size they will be. As an example, weather during the 2014 bloom period was ideal, so we saw some shoots with three clusters on them this year.

Mild-to-moderate shatter in a variety like Grenache isn't always a bad thing. This variety tends to produce large, often dense clusters. The berries that are on the interior of the cluster aren't exposed to sunlight and can therefore stay pale in color, producing correspondingly lighter wines. With some shatter, the more open clusters receive more even light exposure, creating darker and more concentrated wines.  Looser clusters also reduce clusters' susceptibility to mildew, to which Grenache can be prone.

And, of course, bloom is just the beginning.  Crop level and quality are affected by the full season's weather conditions, and we adjust what we do in the vineyard depending on what we see.  Blocks with shatter, or fewer buds per shoot, will need less, or even no, thinning to produce top quality fruit.  The more productive blocks give us more options, but are also more work.

Overall, our unusually cool May appears to have reduced the amount of crop in some varieties, but crop levels on average don't look that different from 2013 or 2014. Given that our last two years produced perhaps the highest-quality back-to-back vintages in our history, knowing that crop levels this year are comparable is a good early indicator of quality.  Stay tuned.


What We're Doing Now: Shoot Thinning

This time of year in the vineyard is a combination of catch-up and get-ahead.  Catch-up because we're still getting the last of the cover crops tilled into the soil, and there are stray blocks, where the work hasn't been completed, whose wildflowers and tall grasses look like remnants of April.  Get-ahead because the work that we do now in limiting the number of shoots a vine has to grow can make a significant difference in both the quality of the fruit that comes off that vine, and in the amount of work we have to do later.

I caught up with Vineyard Manager David Maduena this week to talk about this shoot-thinning work, in a block of Mourvedre whose limited growth (the shoots are only out about eight inches) is a reflection of the cold part of the vineyard in which it lies. You can see the thinned shoots on the ground.

David shoot thinning

All our blocks get their shoots thinned.  We remove lateral shoots (those that are growing out horizontally rather than up vertically) so that air and sunlight can penetrate to where the fruit will hang.  Some blocks, like the Mourvedre block above, also get their numbers of shoots limited if they are showing signs of either weakness or lateness.  Having fewer shoots (and therefore less fruit) means that the vine can ripen the remaining clusters more easily, and with less stress on the vine.  Together, these improve the grapes' concentration and make it more likely that the vine will carry vigor over into the next year. [If you'd like a more thorough and technical explanation of shoot thinning, check out the blog from 2011 where Levi explains the shoot-thinning process.]

Doing this work now, rather than later in the summer, allows the vines to focus their energy on the canes and clusters that will be carried into harvest, rather than wasting resources on growth that will be sacrificed later.  It's also less work, in the same way that weeding a garden when the weeds are small is less work than waiting a few weeks later, at which point they've established themselves.  For contrast, check out the photo below, from July 2011, not long after we hired Levi Glenn as our Viticulturist.  That year was particularly challenging due to the spring frosts, which delay and confuse the vines, and push work that we'd like to be doing now later in the year:

Levi shoot thinning in 2011

Improvements like these in our vineyard practices that Levi, David and Neil have made over recent years are a large part of the reason why I think the fruit that we're getting -- and not coincidentally, the wines that we're making -- has never been better.  2015 looks like it's off to a great start.


Dry Farming in California's Drought, Part 3: How We Got Here (and Where We Go Next)

I was struck by a quote from Tegan Passalaqua, the winemaker at Turley, in a recent article on JancisRobinson.com.  In an interview with Alder Yarrow, Tegan said "In a Mediterranean climate like we have, vertical shoot positioning and 3 by 6 vineyard spacing is basically farming hydroponically".

Hydroponic farming, with its overtones of bland supermarket tomatoes, seems an unlikely candidate to provide the intensity and ripeness that a winemaker would expect from California.  But in its essence, that the farmer is providing everything that a plant needs to bear fruit, I don't think he's far off.  It's worth taking a few moments to understand how grapevines came to be so widely irrigated in California.  In the first part of this 3 part series, I looked at how our understanding of California's climate dictated changes versus what had been done in the Mediterranean.  In the second part, I detailed how we have been farming our vineyard since the beginning to wean it off of irrigation, and what changes we've made in recent years to adjust to the likelihood of a drier future.  In this third part, I will explore how viticulture evolved in California to rely so heavily on irrigation.  If you missed the earlier parts, this article will make more sense after you've read them.

According to Jancis Robinson1, wine grapes were likely first domesticated from their wild progenitors somewhere near where modern-day Armenia, eastern Turkey, and north-western Iran meet, sometime before 4000 BC.  That area is a relatively arid climate, averaging around 400mm of rainfall per year (about 16 inches).  There, grapevines, along with similarly rugged crops like olive trees, were planted on dry, rocky hillsides where the more useful grain and vegetable crops couldn't survive.  This took advantage of grapevines' genetic predisposition to search out scarce water sources, delving dozens of feet deep if necessary.

By 2000 BC, wine grapes had been brought to areas around the eastern Mediterranean, including Egypt, Mesopotamia, southern Greece, Crete and the southern Balkans.  Expansion to areas north and west came over the next two millennia, brought by the exploring and colonizing Phoenicians, Greeks, and (later) Romans.  

High quality winemaking requires the concentration of flavors, achieved through stress on the grapevines and the maturity of fruit.  This happens naturally in the hot, dry climates where grapevines evolved.  But as viniculture moved north through Europe, into climates cooler and wetter than where wine grapes originated, the grapevines faced different challenges. Instead of not enough water, grapevines were challenged with too much water, threatening to dilute flavors.  And the cooler climes meant that lack of ripeness was a significant threat.  The solution to both these problems came in a new way of planting: spacing vines much more closely, so they competed against each other for the available water, and reducing the yield per vine so that the clusters ripened more rapidly.  For contrast, look at the differences in the old world.  An old vineyard in a warm Mediterranean climate (in the example below, Priorat, taken as a still from a promotional video on the Priorat DOQ Web site) might see grapevines three meters apart or more from their nearest neighbors (500 vines per acre, or less):

Priorat

By contrast, a Burgundian vigneron in search of maximum concentration and character might plant grapevines as close together as one meter by one meter (over 4000 vines per acre), and reduce yields per vine from 20-30 clusters per vine to just 3 or 4.  The example below (from Wikimedia Commons) is of a vineyard near Gevrey-Chambertin, in Burgundy, where vines are so close together a tiny tractor can barely fit:

Vineyards_near_Gevrey-Chambertin_(7309858246)

The net result is a can be a greater yield in tons per acre, with increased intensity and a better chance of getting the grapes ripe before the first frost.

It is perhaps useful to think of a grapevine as a small machine, whose roots act as pumps to wick water and nutrients out of the ground.  A vine's leaves absorb solar energy to power this machine. The water that is pulled from the ground is used during photosynthesis as the vine respires through the pores of the leaves, and is also trapped in the plant's tissues and fruit.  Planting more vines into a given plot of land requires more water for photosynthesis to be successful.  If there is enough (or too much) water, this extra density is beneficial and even important.  If there is not enough water, this extra density requires more irrigation to keep photosynthesis going.  And if irrigation becomes a major source of water for the vines, they change their root system to better capture that water source, growing more rootmass under the irrigation drips and less exploring deeper. 

So, is California's climate more like that of the Mediterranean, or more like that of Burgundy?  It depends on what you look at.  In terms of temperatures, you can find both, as evidenced by the success California's winemaking community has had with a a wide range of grapes, from the cool-loving Sauvignon Blanc and Pinot Noir (with origins in the north of France) to the late-ripening Grenache and Mourvedre (with origins in the hot, dry Spanish plateau).  But in terms of rainfall, it should be clear that except for perhaps in extreme north and coastal regions, our total precipitation more resembles the warmer, drier Mediterranean. In fact, many parts of California receive significantly less annual rainfall than the classic Mediterranean climate.  Relatively arid areas like Priorat receive more rainfall than most of the Central Coast, and the rainfall distribution in Paso Robles actually looks more like the Bekaa Valley in Lebanon than it does like Priorat, let alone anywhere in France.  The fact that we receive nearly all our precipitation in the six-month period between November and April only adds to the stress on the vines, and the need for planning if we're going to try to grow grapes without having them dependent upon regular irrigation.

You might wonder why plantings of grapevines in California look more like those in Northern Europe than they do like those of the Mediterranean.  That they do is a relatively recent phenomenon.  A paper on vine spacing presented to the American Society for Enology and Viticulture (ASEV) in 1999 by two winemakers from Robert Mondavi Winery makes for fascinating reading.  Before the late 1980's, most vineyards in California were planted at around 450 vines per acre.  The first large-scale (35 acre) high-density (2170 vines/acre) planting came in Oakville in 1985.  Since then, the paradigm has shifted rapidly, as winemakers found that they could translate the higher density into earlier-ripening, more reliably yielding crops of good intensity.

The downside? It hasn't seemed like there was much of one. More reliable yields, more reliable ripening, and increased intensity all seem like a good thing.  If I find that many of the wines that come from high-density irrigated plantings have a sameness, a fruit-driven thickness and relative lack of soil expression, this doesn't seem to be a complaint shared by many.  And separating out the preference for increasingly ripe flavors that developed over a similar timeframe is difficult (many connoisseurs of Bordeaux, where irrigation is prohibited, have described a similar development over the last two decades). But these higher-density crops can only survive in most parts of California through the regular application of irrigation.  When that irrigation water was cheaply and easily available, the fact that our natural rainfall distribution more resembles the Eastern Mediterranean than Burgundy or Bordeaux didn't seem to matter much. From an environmental standpoint, planting an irrigated vineyard was often a responsible choice for a farmer, as the high efficiency of drip irrigation and the relatively little water that grapevines need compared to a crop like alfalfa offered sustainability in both resource use and economics. But with all of California's agricultural communities engaging in a new level of soul-searching after four years of drought, it's clear to me that the calculus is changing.

Perhaps the solution for a drier future begins with a look at the past.  The old vineyards planted by immigrants in the 19th and early 20th centuries, many of which survived decades of neglect during prohibition and continue to produce a century later, were planted with the densities common to the warm Mediterranean climates (from where, of course, most of the settlers came).  Given our success in recent years replicating these older planting styles, I would hope that one benefit to come out of our current drought will be a renewed interest in low density plantings on deep-rooting rootstocks, requiring at most a fraction of the water of "modern" vineyards. That the wines have turned out to be so good is icing on the cake. 

It doesn't get more sustainable than that.

Footnotes
1 Jancis Robinson's "Wine Grapes" (Penguin Books, 2012) is an incredible resource for anyone interested in the history or characteristics of different grape varieties.