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):

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:

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:

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:

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:

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 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.