NEW ZEALAND: What’s the character behind the cool?

Cool-climate wines, such as Sauvignon Blanc and Pinot Noir, are very fashionable, and New Zealand is widely seen as their New World champion. Sally Easton MW investigates the drivers behind NZ’s wine-growing status

Cool climate is important for its deep-seated implication of potential high quality and longevity in bottle. And New Zealand has adopted the cool-climate mantle for the New World with some aplomb, but is its status as the new world model of cool climate all it’s cracked up to be?     

The country is over 1,000 miles long. That’s longer than Italy, where growing conditions vary from cool, Alpine valleys in the north to scorched Sicilian shores in the south. No one would suggest that all of Italy is cool climate, though bits of it seem to fit. New Zealand tracks a similar trend from a significantly warmer Auckland to a notably cooler Central Otago.

Model of cool climate?
Degree days and MJTs (see box) are regarded as a sound starting point for climate and viticulture. But degree days are not always a reliable indicator in NZ. As Ivan Donaldson, of Pegasus Bay Winery in Canterbury, points out, “Degree days here [Canterbury], in Marlborough, and in Martinborough are about the same, but we harvest later than Marlborough. Also the highest ever official temperatures in NZ were recorded here in Canterbury at 43°C.  We have regular days at 30° to 40°C. Auckland achieves 30°C once every 20 years. But Auckland is warmer on average than here.” Degree days and MJTs are clearly only part of the picture.

High diurnal temperature fluctuations during the ripening season are a common theme for New World wine regions. They’re not a particular feature of Mediterranean climates, nor of maritime temperate climates such as Bordeaux. According to Jackson Estate’s winemaker, Mike Paterson, the diurnal temperature fluctuation “that we experience in NZ is one of the things that makes NZ unique. During ripening we get 5-6°C nights and warm 31-32°C during the day. It’s the temperature difference that drives the metabolism and flavour profile of the fruit”.

Added to this, the sun is strong in New Zealand, so warm to hot days and long sunshine hours may be one thing, but the strength of the sun is another. It is said that 20 minutes in the sun in New Zealand will burn you quicker than 20 minutes almost anywhere else in the world. Blair Walter, winemaker at Felton Road, says: “Solar radiation is higher in Central Otago than in northern Europe. The earth is closer to the sun during the growing season and the ozone hole causes higher levels of UV radiation than in the northern hemisphere.”

Whether these factors have any connection to the conundrum of New World “cool climate“, combined with high alcohol, may be a moot point as alcohols have been rising here as much as any region in recent decades. However, winemakers argue high alcohols are a temporary thing while they get to grips with the NZ model. “Alcohol is a dilemma” says Rudi Bauer, winemaker at Quartz Reef, “physiological and sugar ripeness don’t go hand in hand. We need better vineyard management, and vine age. With more experience we will learn how to handle it.”

It is easy to forget how young a viticultural region New Zealand is. It was made even more youthful by the recent arrival of new and better-suited clonal material.

Site selection
It is known that some of the best vineyard sites in the Médoc owe their proximity to the Gironde, where a bit of reflected warmth from the water late in the ripening season can be significant. And without the steeply inclined slopes of the Mosel, which maximise insolation, Riesling would struggle to ripen.

With New Zealand’s strong sun and warm days, moderating influences are more about site selection for cooling influences during the heat of the day, despite its baseline cool-climate position.  Waiheke Island has a very warm climate, with small diurnal variation, and extreme heat has been known to give cooked flavours to wine. Cooling breezes compensate in part, but the island has adapted its varietal mix to the warmth with Syrah, Cabernet Sauvignon, Merlot, Chardonnay and Viognier. The island is hilly, so, says Matt Allen, vineyard manager at Man O’War Vineyards, “we use south-facing slopes [away from the sun], which are sub-optimal for sun and light intensity for our whites, and the reds are on warmer, north-facing slopes”.   

Sitting at the bottom of North Island, Martinborough has no protection from the cold southerlies coming up from the Antarctic. These cold southerlies influence Marlborough as well, and can whip through the Cook Straits towards Nelson. Mike Trought, research leader at Marlborough Wine Research Centre, says of Marlborough Sauvignon Blanc: “The Awatere has smaller diurnals [than the Wairau], it’s cooler and can get southerly blasts which give tomato stalk and gooseberry characters, as well as vivacity.”

Rippon Vineyard (Central Otago, Lake Wanaka) is another case in point. Owner Nick Mills says: “The thermal mass of Lake Wanaka is 13°C in winter and 15°C in summer. We have hot days, with an average temperature of 30°C, but we get a cooling breeze from the lake. And the lake moderates our frost risk. We’ve had only three serious frosts in 25 years.” He adds: “Ruby Island [in the lake] blocks or rather ‘spoils’ the norwesterly winds a bit, it helps to dissipate the wind. The island is a very important part of our mesoclimate.”

 
Regional identity
Developing among all of this is the emergence in New Zealand of real, identifiable, regional character, which includes an improving matching of grape varieties with site. Clear trends are emerging, such as Chardonnay, Viognier, Bordeaux reds and Syrah from the warmer North Island; Pinot Noir moving to slopes in Marlborough for better expression; and, indeed, different expressions of Pinot Noir depending on its regional origin.  

The greater humidity towards the north of NZ enables quicker ripening. In Hawkes Bay, says Tim Turvey of Clearview Estate, the climate is “cool, more temperate daytime temperatures with warm night time temperatures. We get sea breezes all day and the temperature doesn’t drop at night.” This suits “warmer” grape varieties and Hawkes Bay has over 80% of NZ’s plantings of Merlot and Cabernet Sauvignon, and, on a smaller scale, Syrah. And it is Syrah that’s creating all the excitement as the later-ripening Cabernet Sauvignon declines slightly. At the 2007 Air New Zealand wine show, the Champion Wine of the Show Trophy went to Syrah for the first time – Trinity Hill’s Homage Syrah 2006.

Regional flavour differences
Aromatic varieties such as Riesling, Pinot Gris, and Gewürztraminer are beginning to make a name for themselves in Nelson, where, says Hermann Seifried, “the climate is temperate, with an ocean influence. Hot for us in summer is 24°C to 25°C”. And this, despite the region claiming to have the highest sunshine hours on average, in NZ. Seifried is impressed with the mouthfeel and extract achievable in Nelson and he plans to plant 1,000 Gruner Veltliner vines during 2008, one suspects harking a little to his Austrian heritage as well as the inherent quality of the grape variety.

But it is Pinot Noir where most regional flavour differences are coming to light, in those regions where it’s found a natural home: Martinborough and Wairarapa, Marlborough, Canterbury/ Waipara and Central Otago.

Part of this evolution is very recent, and comes alongside new clones, and changes in winemaking practice. Bill Spence, founder and general manager of Matua Valley Wines, says: “For many years people tried to make Cabernet Sauvignon out of Pinot Noir. It changed when Montana moved to Blenheim, which was thought to be the place for sparkling wine – but sparkling wine clones were planted. Then people tried to make Pinot Noir from bubbly-production clones. New clones arrived only 10-12 years ago resulting in a new wave of new wines.”

Pinot Noir is the new, bright thing for Marlborough, but only since plantings have been moving off the flats. Neill Culley, managing director and winemaker of Cable Bay in Waiheke Island, says: “Pinot Noir in Marlborough took longer to establish because the plantings were in the wrong place – on flat paddock next to Sauvignon Blanc.  The good sites are up in the hills. Marlborough is now one of the top Pinot Noir producing sites in NZ.”

Regional differences are apparent, as Jeff Clarke, chief winemaker of Pernod Ricard, explains: “Flavour profile tends to reflect the mesoclimate – Marlborough has the lightest, red berry fruit, tending to strawberry, more aromatic, fruit characters, with soft tannins. “Martinborough/Wairarapa shows fulsome plummy fruit with a round and robust structure.” In Waipara, he said the characters are more earthy, dense, brambly and Central Otago is pure, linear with dark cherry, wild thyme and attractive herbal characters.

But the best is yet to come, as vines age. Most Pinot Noir vines, especially the new clones, have been planted only in the last 10 years. Winemaker at Mt Difficulty, Matt Dicey, says: “Mt Difficulty has some of the oldest vineyards [in Central Otago], from 1992 to 1994. [We developed the label] Roaring Meg as somewhere to put the young fruit. There is a clear cut between depth and concentration for Mt Difficulty – from year 10 we start getting concentration and complexity.“

 
Marketplace pragmatism
Built into growing regional identities in New Zealand is the need for producers to draw on fruit from those distinct regions in order to offer the market key styles well regarded on the international stage. Producers outside Marlborough, such as Matua Valley and Cable Bay, must offer a Marlborough Sauvignon Blanc in their range, even if it means buying in expensive fruit, or having operations in Marlborough. Hawkes Bay Sauvignon Blanc may be a more economical item, with its more rounded and softer palate than Marlborough, but it simply doesn’t cut the mustard with customers who are looking for that benchmark zingy identity conferred by the Marlborough region. Central Otago Pinot Noir is becoming another “must range” for producers.

Uniquely NZ
Regardless of cool or cooler, marginal climates and clear differences along the 1,000 mile north-south stretch that is NZ, Bauer strikes a chord for New Zealand, saying: “Our strongest card is our fruit – its clarity and the expression of that clarity. It doesn’t matter
which grape variety. It is the core of our country. Germany has acid/residual sugar balance, Italy has tannin/acid balance. We need to learn how to harness our fruit so it’s stylish and extraordinary.”

db © August 2008