Having made wines now over 24 vintages there is one ‘truism’ that is irrefutable in a cool climate like Tasmania and that is- not all vintages are the same. We have seen magnificent vintages producing stunning wines and dismal vintages that you want to forget. But I want to discuss the ‘the good, the bad, and the downright ugly’ from a point of ‘realism’.
Different grape varieties ripen at different times in the season. Some varieties, like the Pinot family, ripen early. Some, like Merlot and Malbec, ripen mid-season and others like Shiraz and Cabernet Sauvignon ripen later. In cooler seasons there may be 5 weeks difference between dates for early and late varieties for a similar sugar level (ie ripeness).
In warm climates, like McLaren Vale in South Australia or Margaret River in West Australia, most varieties ripen dependably every year with minor variation in harvest dates. But in Tasmania there are large variations in vintage dates and true physiological ripeness is not assured each year. In some years, grapes can fail to achieve full ripeness before leaves colour and fall off, ending sugar accumulation.
Of course it depends on what the winemaker aspires to…sparkling base wine from just ripe Pinot Noir or Chardonnay or fuller bodied styling of Bordeaux varieties. Suddenly the site selection and the peculiarities of the season make all the difference, every additional degree of temperature advantage makes a difference in a marginal climate like Tasmania.
Establishing a vineyard in Tasmania requires an understanding that even with the best planning, some vintages can challenge beyond the limits of winemaking and hard decisions need to be made. Although global warming is making harvest dates move forward as the accumulated heat rises over the season, thus making it easier to ripen mid-season grapes, there still seems to be decadal outlying vintages that make things near impossible. This year, 2020, has joined the infamous 2011 and less remembered 2004 and 1996 vintages.
As in 2011, we have decided not to harvest our grapes. We could make wine this year but the ‘quality’ that we want for our brand won’t be there. So rather than disappoint our customers and tarnish our brand we have chosen not to proceed. The logic is strengthened when considering the business conditions during the corona virus lockdown and the fact that we have some great wines waiting in storage which are as yet ‘unreleased’.
The ‘great’ vintages (across all our varieties) for us have been 2000, 2005, 2008, 2013, 2018 and 2019.
What makes a ‘great’ vintage? For us, as we don’t irrigate, an early pattern of budburst, rapid spring growth with warm days punctuated by some decent falls of rain, a spell of heat in late January in the low 30’s followed by a long dry autumn to deliver early harvests of clean fruit before the autumn ‘break’ of rains. It’s the luxury of being able to hang the fruit out to achieve maximum ripeness to get layers of flavour in the finished wines that we really want.
But what about the vintages that fall between the ‘great’ and the ‘disastrous’? There can be different pathways to any set level of sugar ripeness delivering quite different wines at the same alcohol level. This is because there are many flavour compounds coming together to make a wine’s aroma and flavour and each of these compounds are created by enzymes that operate most efficiently at different temperatures during ripening. Patrick Iland explains this well in his book “Australian Wine, Styles and Tastes” (2017). As an example, for Chardonnay, depending on the temperatures during ripening from cooler to warmer, the flavour profile can vary through gooseberry, apple, quince, melon, nectarine & finally to tropical flavours of pineapple and guava.
Each variety has a spectrum of potential flavours that can be expressed, depending on the temperatures experienced in the last months of ripening following veraison (colour change). So, for a Merlot wine at 13% alc. from a cooler year you may see elderberry, black olive and blueberry characters but in a warmer year, you may see plum, cassis and fruitcake characters.
Cooler years deliver higher acid levels at harvest, which coupled with lower alcohol (alcohol tastes sweet), can seem unbalanced. The enzymes I have previously mentioned, involved in flavour production are also less active overall at cooler temperatures so that the total intensity of flavour is less in the coolest years. Cooler years are often accompanied by heavy autumn rains that can swell the berries and dilute the flavour components & reduce the sugar level. Worse still, they can trigger an outbreak of botrytis mould that can damage both colour and flavour.
Finally, for red wines, the tannins and colours will be reduced in cooler years despite the sensation of the tannins being more obvious for two reasons. The first being that acidity enhances the astringency sensation and secondly the nature of the tannins developed under cool conditions have a harder, coarser and potentially bitter character. For a wine to cellar well you want plenty of ripe velvety tannins, some fresh acidity and stacks of layered fruit and savoury characters.
Hopefully I have given you some greater insight into vintage variation from our site here at Grey Sands and why we have spared you from vintages like this one!
‘Weather’ (as opposed to ‘climate’) is highly variable in Tasmania…eg there are many times when Exeter (which is only 7kms from us) may be in sunshine & we’re having rain…or vice versa! You need to read my comments as being specific to our site and varieties and not as a comment on the whole of Tasmania’s wine growing areas.