Seasonal variation and quality

It’s clear just by glancing through this book that the same grapes from the same vineyard invariably produce very different wines from year to year. Although vintage variation in Australia is merely a fraction of that encountered in most European wine regions of any quality, it is still a significant variable that demands consideration when making informed buying decisions.

Even in the event that all other variables are consistent from year to year, which they certainly are not, weather provides the greatest single influence in wine quality and style from season to season. Weather can influence wine in an infinite number of ways, from determining whether conditions at flowering are favourable or not, all the way through to whether final ripening and harvest occur in the warmth of sunshine or through the midst of damaging rains. If viticulturists were to turn pagan, it would be to a god of weather that they would build their first shrine.

Weather-influenced variation is nearly always more pronounced and more frequent in the cooler, more marginal viticultural regions. While Australia is principally a warm to hot wine producing nation, a significant proportion of the country’s premium wine now comes from cooler regions in the southwestern and southeastern corners of the continent. The spectrum of diverse weather encountered in these regions far exceeds that of the traditional Australian wine growing areas like the Barossa Valley, McLaren Vale, central Victoria and the Clare Valley. Paradoxically, the best years in cool climates are typically the warmer seasons that accelerate the ripening period, creating a finer acid balance, superior sugar levels, flavours and better-defined colours.

Variety by variety, this is how Australia’s premium wine grapes are affected by seasonal conditions:

White wines

Chardonnay. Cool years cause chardonnay and most white varieties to accumulate higher levels of mineral acids and to result in lean, tight wines with potential longevity, provided they have sufficient intensity of fruit. Cool year chardonnays can display greenish, herbal flavours, and can resemble grapefruit and other citrus fruit, especially lemon. Warmer year wines become richer and rounder, with fruit flavours more suggestive of apple, pear, quince and cumquat. In hot seasons, chardonnays become faster-maturing wines with flavours of peach, cashew, melon and tobacco.

Riesling. Although riesling does not need to ripen to the sugar levels necessary for a premium chardonnay, cool-season riesling tends to be lean and tight with hard steely acids, possibly lacking in length and persistence of flavour. Better rieslings from superior years have succulent youthful primary fruit flavours of lime juice, ripe pears and apples, with musky, citrus rind undertones. Significantly broader and less complex than wines from better seasons, warmer year rieslings tend to mature faster, occasionally becoming broad and fat on the palate after a short time.

Sauvignon Blanc. Cool season sauvignon blancs tend to be hard-edged wines with steely acids, with over-exaggerated and undesirable herbaceous flavours suggestive of asparagus and ‘cat pee’, a description for which I have yet to find a polite alternative nearly as succinct. The warmer the season the riper the fruit becomes and the less grassy and vegetal the aroma. The downside is often a reduction in the intensity of the wine’s primary fruit flavours. Expect sweet blackcurrants, gooseberries and passionfruit from sauvignon blancs in good seasons, with at least a light capsicum note. Warmer seasons create broader, occasionally oily and less grassy wines, with tropical fruit flavours suggestive of passionfruit and lychees.

Semillon. Semillon tends to react to cooler seasons by creating very tight, lean wines with more obvious grassy influences, but perhaps lacking primary fruit character. On occasions, these rather one-dimensional young wines can develop stunning flavours in the bottle over many years, as classically unwooded Hunter semillon proves time and again. The proviso is that they need length on the palate while young.

Red wines

Cabernet Sauvignon. A late-ripening grape variety which reacts very poorly to cool, late seasons, cabernet sauvignon has traditionally and wisely been blended with varieties like merlot in Bordeaux and shiraz commonly, until recently in Australia. Cool season cabernet sauvignon makes the classic doughnut wine: intense cassis/raspberry fruit at the front of the palate with greenish, extractive tannin at the back and a hole in the middle. Under-ripe cabernet sauvignon reveals less colour and a thin, bitter finish. Its tannins are often greenish and under-ripe, tasting sappy or metallic, while its flavour can be dominated by greenish snow pea influences more suggestive of cool-climate sauvignon blanc.
Warmer seasons create much better cabernet, with genuinely ripe cassis/plum flavours, a superior middle palate and fine-grained, fully-ripened tannins, although a slight capsicum note can still be evident. In hot years the wines tend to become jammy and porty, suggestive of stewed, dehydrated prune and currant-like fruit flavours and lacking in any real definition and fineness of tannin.

Pinot Noir. Pinot noir does not react well to very cool seasons, becoming herbal and leafy, with a brackish, greenish palate and simple sweet raspberry confection fruit. Warmer seasons produce the more sought-after primary characters of sweet cherries and plums, fine-grained tannins and spicy, fleshy middle palate. Too warm a season and the wine turns out to be undefined, simple and fast maturing, often with unbalanced and hard-edged tannins.

Shiraz. Thin and often quite greenish – but rarely to the same extent as cabernet sauvignon – cool-season shiraz often acquires leafy white pepper characters, with spicy, herby influences. Provided there’s sufficient fruit, which may not be the case in wine from cool seasons, it can still be a worthwhile wine, although not one likely to mature well in the bottle, especially with metallic, sappy and green-edged tannins. Warmer years create shiraz with characteristic richness and sweetness, with riper plum, cassis and chocolate flavours and fully-ripened tannins. Hot year shiraz is often typified by earthy flavours suggestive of bitumen and leather, with dehydrated prune juice and meaty characters. Please login to post comment