September and October 2010 Douro Insider

First day of harvest at Malvedos: late afternoon clouds and rumbles of thunder, but not a drop of rain

In retrospect it is hard to know what to make of the weather over the vintage period this year.  Almost certainly it is fair to say that some rain at the start of September might have been quite beneficial for ripening.  Probably if temperatures had also been a little cooler for the first two weeks of the month then the maturation of some varieties would have been improved.  But on the other hand, the forecasts leading up to the start of the harvest, and during the first few days of it, were extremely volatile and threatened all sorts of trouble which fortunately never materialised.  There was a whole series of tropical storms or hurricanes that basically brewed up around the Caribbean and proceeded to cross the Atlantic in a merry parade but, if and when they made landfall in Iberia, they no longer had enough energy to make it over the Marão.  In that respect, we were extremely lucky. 

It did finally rain during the first week of October (which was of course too late to influence maturation) and this could certainly have spelt trouble as the grapes are starting to become more susceptible to rotting by this stage, but again we were lucky as it dried out quickly.  In the end, barely a single mouldy grape was seen all harvest.  So whilst the weather wasn’t exactly perfect, it turned out to be a lot less dangerous than was being forecast almost on a daily basis.  In the words of one astute online commentator, it was in many respects ‘the vintage of dodged bullets.’  Things could have been, and perhaps should have been, a lot worse.

After the complete drought that had held throughout the months of July and August, a change came on the very first day of the September.  It actually rained a little in the Douro, albeit with a very localised pattern of distribution.  In most places no more than a few drops fell, or none at all, but in parts of the Douro Superior the intensity and duration of the shower were such that possibly just enough rain fell to have a small beneficial effect on the grapes.  In Alijó, however, this bad weather actually materialised as a hail storm with predictable damage, heartbreakingly close to the harvest.  On the coast, in Porto and Gaia, the nights started to cool somewhat and the morning mists made their return, but upriver the only relief was the occasional dewfall occurring as a result of the wide daily range of temperatures.  The days stayed remarkably hot:  there were four days in excess of 35º C during the first half of the month in Pinhão, and six in the Vilariça valley (in the northeast Douro Superior).

There was some rain in Gaia on the 6th September, but no penetration inland, and things in the Douro stayed fine until the middle of the month.  The weather then started to tease us a little.  What started off as a lovely sunny day on the 15th suddenly turned very windy at around midday and before long gusting spirals of dust were spinning from one terrace to the next.  It turned threateningly humid and rapidly clouded over but in spite of the thunder there was no rain.  By this stage it was a relief as some farmers were starting their harvests and it was probably too late by then for precipitation to be beneficial.  The atmospheric uncertainty continued, eventually raining a bit on the 17th, but the layers of dust soaked up the water before it could get through to the rootzone.  It stayed thundery for another few days, and again teased us with a tiny speckling of raindrops on the 20th, the very day that many of the wineries opened.  Thereafter sunny weather predominated for the rest of the month, at least ensuring that the bunches stayed dry and disease-free.

28 Sept at Malhadas: clear, sunny, hot, and the tractors move in a cloud of Douro Dust

A comparison with the long-term mean reveals that temperatures were almost spot on the average for this time of the year and varied relatively little across the region.  The September mean for Pinhão was just 0.2º above the average, at 22.0º.  What is interesting to note is quite how hot the daily maximum was at times – in excess of  37º C (100º F) near Tua, for instance.  Furthermore, the nights were relatively mild, meaning that September was the sixth warmer than average month in a row.  Precipitation was just a quarter of what was expected (11 mm, compared with 40 mm) and there was never really enough rain to influence the fruit in any way, for better or for worse.  According to official statistics, it was the driest September in Portugal for 22 years, although oddly enough the Instituto de Meteorologia made the same claim last year.

Late September’s generally fine conditions continued, with perfect vintaging weather until the 3rd October when all of a sudden the weather broke dramatically with very strong gusts of wind and pounding rain.  The storm brought down buildings in Gaia and there was detritus all over the roads in the north of the country.  Mercifully the vineyards escaped another bullet unscathed.  Things improved for a couple of days, drying the fruit out, but then another violent front rolled in on the 6th and 7th.  Fortunately again it passed without detrimental effects.  Thereafter it was remarkably benign for the rest of the month; there were one or two days that started a little cloudy but basically it stayed clear and sunny to the end.  Obviously the nights started to cool down quite a bit as the days shortened, but up until then they had been surprisingly mild, even at high altitudes.  The month finished on something of a sour note, however, with terrible weather spoiling the very last weekend.  Worse still, it was a long one with a public holiday tacked on.  The rain was fearsome, and flooded large low-lying parts of both Lisbon and Porto.

Principally as a result of two or three large storms (rather than a slow and steady trickle) the month produced rainfall 50 % above average in Pinhão (114 mm, compared with 76 mm) and the agricultural year therefore came to an end with yet another month of above average precipitation.  This was the eighth such month out of the last 12, and means that we finish up with a very positive moisture balance in spite of the hot and dry summer.

The total precipitation figure for Pinhão came in at 933 mm which, after three below average years, compares very favourably with the mean of 675 mm.  As was pointed out back in March, never before had we recorded six months in a row with over 100 mm of precipitation, and it was without a doubt this much-needed replenishment of the water table that saved the vineyards from the desperately tough conditions in July and August which otherwise could have been disastrous.

When it comes to temperatures, the graph below shows clearly that October was just the third month of this agricultural year with a below average score; in this case with the monthly mean clocking in at 15.4º, over a degree cooler than the long term mean (16.7º).  The bars on the graph are plotted on the left hand axis, and the mean curve on the right.  In spite of this, the overall annual average was actually only very little above the long term mean, registering 16.2º compared with 15.9º.  The reason for this was, perhaps, that the three very hot months were practically cancelled out by three very cool ones.  The other temperatures were only very slightly positive.  Again this points to more extreme conditions and more variable weather patterns than usual, a trend that we have mentioned before.

One thing that was already clear very early on in September was that the harvest was going to be a late one.  A combination of two factors (the above average yield and the very hot conditions in August) meant that relatively little sugar had been produced by the vines so far, which needed to be distributed between more bunches of grapes.  So predictably the final phase of maturation was slow, and few quintas started picking port grapes much before the 20th September.  This meant that we had a little more time than usual on our hands, as there is really nothing we could do at that stage but wait.  One useful activity that makes harvesting much easier, when the time eventually comes, is a good pre-emptive desponta.  Removal of the shoot tips, especially where they are threatening to close up the inter-row space, is essential to allow smooth passage through the vineyards both for  picking and for carrying out the buckets of grapes.  It also goes some way towards making the bunches more visible, which could have a small effect on speeding up the picking process.

Where the desponta is carried out mechanically the workforce is freed up for other jobs.  Looking ahead, beyond the vintage, many quintas took the opportunity to tidy up the olive groves.  Olive picking involves extending nets on the ground beneath the trees to catch the falling olives so any high vegetation must be mown back first, usually with strimmers.  Immediately before the grape harvest can be a good time to do this.  At most quintas at least two or three workers would be spared such activity as the wineries obviously need to be prepared for the harvest too.  This last-minute maintenance involves setting up all the non-fixed equipment and machinery, and thoroughly cleaning and sterilising everything from the reception area to the storage tanks, including all the pumps and hoses.

Once the wineries and all the equipment is sparkling cleanly, the order is given and the harvest begins for real.  It is something of a truism, but often repeated with some justification, that there is no such thing as a normal vintage.  The rule held this year too – it was not a typical harvest.  Firstly, it was a very long one, with some quintas picking grapes for a full month.  This figure does reveal some difficulty in arranging pickers, but reflects more on the sheer quantity of grapes hanging on the vines.  For many properties it was one of (if not the) largest harvests ever.  Every year we would expect average yields per vine to increase modestly due to the fact that unproductive old vineyards are constantly being replaced with higher-yielding (although less densely planted) modern vineyards, more of which come online every year.  Nevertheless, 2010 exceeded even these expectations, with an average production of around 1.5 kg per vine.  Of course this is hardly very much by the standards of the rest of the viticultural world, but it is a significant amount for the Douro.

Pickers at Tua 8 Oct: again threatening clouds, but no rain, and we brought in a good crop of Francesa that day

The other major difference from a ‘normal’ year was that the picking order was altered strategically as a result of the unusual ripening patterns of the various varieties.  Usually speaking the vinhas velhas are the first to be picked, followed by the Tinta Barroca.  The Barroca quickly attains high levels of sugar, in part due to the fruit’s tendency to dehydrate, thereby concentrating the juice.  Next up we would normally move onto the Touriga Nacional, but this year early in the season the flavours were still rather green and the sugar levels below that which we would have hoped for.  To give it more time to ripen it was pushed right back into penultimate place, and every other variety, barring the always late-ripening Francesa, was picked first.  This kind of flexibility is essential in order to get each casta (variety) at its best, and we were fortunate that no sign of disease was seen throughout the harvest.  Timing was critical this harvest, and those who got it right made some very good wines indeed.

As usual, once the last of the fruit is in the lagares and the buckets are all washed up and put away, the vineyard workforce gets a well-deserved rest with a week or two of holidays.  Many will use this time to pick their own grapes, or help out family members with their individual harvests.  By the time all of this was finished there was little else that could be squeezed in before the end of the month, but once back at work it was still quite early to start pruning.  In some cases we turned our attention to the olive groves again (if we hadn’t finished with them before the vintage).

As it is a relatively quiet time of the year one of the best uses of the rapidly dwindling daylight hours is getting a head start on next year’s vineyard plantations.  This means that any block destined to be replanted needs to be ripped out before we can get the heavy machinery in.  In practical terms there is a considerable amount of manual work required – first the vines must be cut off the wires, and then the trellis wires are cut, pulled out and coiled up ready for recycling.  The old stone trellis posts are pulled out, and a digger then removes the vines.  These are collected up to be used as firewood, or often they are given away to anyone from the local villages who wishes to come and collect them.

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4 thoughts on “September and October 2010 Douro Insider

  1. Dear Graham

    My husband and I love your port but we would really like to know more about the bottles! As a scientist my husband was trying to work out how you produce the raised “badges” at the neck of the bottle? He has an idea, but it would be good to hear the truth directly from the horse’s mouth.

    Many thanks.

    1. Hello Jane, I am planning to write about our bottles in the next month or two, I will be sure to look into this for you as I do my research. Thanks for the query.

  2. Miles,
    I always look forward to these reports and I know they take a lot of work to produce, so thank you! Looking forward to the next one already.

  3. Thanks Andy.
    It’s rewarding to have some feedback, so I appreciate your comment. I can’t promise when the next report will be ready as I’m pretty busy with the bulldozers at the moment, preparing the terrain for next year’s new plantations.
    Best wishes,
    Miles.

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