Our Recipe for Great Pinot Noir

This could be a pretty long debate, but it seems to us that there are a small number of key requirements for keeping Pinot Noir happy:

Growing Season Sweet Spot

GDD’s (Growing Degree Days) are measured in a few different ways so numbers are hard to compare, but the way we do it, 850 – 1100 in the growing season seems to be the sweet spot for Pinot Noir. In latitude, that generally means being at about 45-47º North or 44-45º South, (the Antarctic mass makes the Southern Hemisphere a touch cooler, so the band is a little farther North there).

Warm Days, Cool Nights

A significant variation between maximum and minimum temperatures each day. Hot days, (but not too far above 30ºC), and cool nights, develop flavour complexity. That means being a continental rather than a maritime climate, but not so far from the sea that the frosts become untenable.

Long, Cool, Dry Autumn

Hang time seems to really improve Pinot Noir. A microclimate that gets the fruit nearly ripe, then cools off and lets it hang for a while seems to add depth to the wine. But Pinot Noir is very susceptible to Botrytis, so low humidity and low rainfall in the autumn is a big plus.

A Heavy but Draining Soil

In Burgundy, the combinations of Clay and Limestone achieve this. We have heavy Loess soils interspersed with gravels. Either way, the roots have heavy soil with good minerality and low organic matter, but don’t get waterlogged.

It might seem surprising that given such a short list, there aren’t a lot more places which fit this recipe for Pinot Noir viticulture. But a quick look at the world map shows why.

To get the diurnal shifts you need to be inland from the coast, (though the Californians get them through coastal fogs) but if you are too far in from the windward coast, the shifts get too great and frosts in Spring and Autumn get too dangerous. In the Northern Hemisphere there are only 2 continental masses: go inland on each, following the prevailing winds, from 45-47 degrees, moving eastward until the climate gets continental and you arrive at The Williamette Valley in the USA and Burgundy in Europe.

Try the same exercise in the Southern hemisphere and there are similarly only 2 land masses, one is Patagonia, where it is too windy to grow grapes. The other is Central Otago.

Our Unique Climate & Soils

Central Otago’s climate is positively weird! Locked in deep valleys, surrounded by snow covered mountains, the vineyards have very low rainfall, (40cms per year at Bannockburn), though just 120 kilometres to the West, Milford Sound is the second wettest place on Earth with around 28 feet of rain being often seen in a single year.

This proximity to very heavy rainfall means that we have large amounts of water available, but not a lot of it comes from the sky. The very low humidity (30-40%, typically) means that Botrytis rarely causes problems and gentle anti rot regimes can be easily achieved.

Long days and very little cloud add to the heat summation. Peak temperatures are often around 31-32º in the summer, but the nights are cool - one day last year we measured 33ºC maximum and 3ºC minimum in one 24 hour period!

“Some people talk about “terroir”. We think we’ve got some pretty good "dirt.”

Our soils are moderately old (often windblown Loess), formed over successive ice ages as the glaciers ground Schist rocks to a fine flour. Layers of Loess of various depths are interspersed with river gravels. Add to these sandier soils, formed by water erosion and the viticulturist has a spread of challenges and opportunities.

Loess is highly prized in every winegrowing region where it is found: it seems to bring out complexity in many varieties, but there is no question that Pinot Noir and its relatives thrive on it. While it is very fine and heavy,the Schist particles from which it is made are glass like, and do not readily form clays.

The soils are therefore free draining, even when they are heavy in texture. The low rainfall has kept leaching effects low, so there is a good level of mineral compounds present, but the low rainfall has kept plant growth sparse, which means the organic content of the soils tends to be low. The result is a soil low in vigour, but high in mineral richness, with the ability of the viticulturist to use irrigation as a finely tuned control; keeping vines at exactly the desired degree of controlled stress, to provide optimum fruit quality.

Interestingly there often seems to be a correlation between favoured planting sites and abandoned gold mines: possibly some of the geology that attracted the miners also suits the vines.

A Clean Environment

“If I were a grape, this is where I’d want to grow up”

45 North and 45 South are very different worlds. In the temperate zones, global winds flow West to East round the planet. In the North that journey takes them through heavily populated and industrialised regions. In the South, there is only Central Otago and Patagonia. While well over 100 million people live between 44º and 46º North, there are less than 400,000 living in the Southern strip. This reflects in a lack of pollution and disease pressure - there is no vineyard in Central Otago within 200 kms of a traffic light!

We believe the natural health of our vines is a reflection of our isolation. It may be a bit quiet in the evening, but the grapes don’t mind that!

Thanks to the industry body Central Otago Pinot Noir Ltd for this explanation