Central Otago is New Zealand’s coolest wine region, and with its location almost at the bottom of South Island, it is the world’s most southerly wine region. The centre of the region is on the 45th parallel, which is the same as Bordeaux, but the climate is similar to Burgundy. Pinot noir seems to do well when it is right on the cusp of viability, and that is certainly the case here in the south.
The district’s potential as a wine growing area was recognised by visiting French and Australian viticulturists from the 1860’s onwards. At that time, the region was in the middle of a gold rush, and a small quantity of wine was produced. However, after the gold dried up and the miners trickled away, wine grapes were not commercially grown again in Central Otago for more than a century.
Modern day wine growing began in 1972, and in 1975 experimental plantings went in at Rippon Vineyard, Lake Wanaka. The first commercial release of a pinot noir from Central Otago was the 1987 vintage from pioneer Alan Brady at the Gibbston Valley winery.
Since then, vineyards have rippled out across the region, and today, Central Otago is internationally recognized as one of the few places in the world where the pernickety pinot noir variety has found a home outside Burgundy. Many of the world’s top wine writers have recognised this fact:
‘Many believe this is where the pinot grail is to be found’ (Jancis Robinson – Wine Atlas of the World)
‘Tuck into Central Otago pinot noir, at last Burgundy has a serious New World rival’ (Jane MacQuitty, The Times, October 11 2003).
‘This is God’s country when it comes to pinot noir’ (James Halliday, Panorama 2000)
Where as most of New Zealand’s wine regions have a maritime climate, Central Otago is inland with a dry, semi-continental climate. Here we experience greater daily and seasonal extremes of temperature than found elsewhere in the country.
Often referred to as ‘vineyards on the edge’, the landscape is dominated by majestic snow-capped mountains and rolling deep valleys, and is centred around the Kawarau and Clutha Rivers and Lake Dunstan. The vineyards are the highest in New Zealand. Plantings range from 200 to 400 metres above sea level, and the altitude helps keep things cooler.
The continental climate leads to large diurnal temperature shifts – temperatures can range from plus 30ºC during the day down to below 0ºC at night. The hot days and cool nights are one of Central Otago’s best attributes in growing grapes, developing flavour, complexity and intensity. A slow ripening, with a long ‘hang time’ on the vine, is perfect for pinot. The cool nights also help grapes retain acidity, which aids the stability of the wines.
Central Otago has a very low rainfall of 325-600mm per annum, getting wetter as you go west. In fact, the second wettest place in the world is only 120 km to the west, in Milford Sound. However, the huge barrier of the Southern Alps halts the rain, leaving us quite dry in the east. This low rainfall and very low humidity mean fungal and rot problems are minimised, but irrigation is on standby. Pinot noir is very susceptible to Botrytis, so low humidity and low rainfall in the autumn is a big plus.
During the summer, the days are often hot and long. There’s very little cloud cover and temperatures peak in the high 30’s. Sunburn can be a problem for the workers and grapes alike. The Cromwell sub-region where Wooing Tree is situated achieves higher temperatures largely due to a lower altitude than other cooler sub-regions.
Frost is one of the main risks when growing grapes in Central Otago. Heavy frosts occur throughout winter, and they can also cause problems during the growing season. They are not unheard of in the summer months. Most vineyards employ some form of frost protection, be it planting on a slope or the use of helicopters, wind machines, frost pots, or water sprinklers.
At Wooing Tree, we use Flippers, a type of water sprinkler which allows us to minimise the amount of water we apply and direct it along the rows. It’s a very interesting juxtaposition that water forming an ice crystal around the vines will stop them from freezing right through! The latent heat energy given off during the process is enough to hold off Jack Frost. It is not uncommon to frost fight well after bud burst and before harvest in the autumn.
High wind can be a problem, usually around October and November – this requires careful and timely canopy management by keeping the trellis wires lifted to support and protect the new shoots.
Central Otago soils are moderately old – often windblown loess – formed over successive ice ages as the glaciers ground schist rock 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 odd patch of clay, and the viticulturist has a spread of challenges and opportunities.
Wooing Tree soil is of the sandier type over a gravel base. This light, free draining soil gives us greater control over our irrigation programme, as we can keep the vines just above the stress point, and water as needed. We also use the irrigation system to fertigate the vines in a little and often method.
There are two distinct sides to the vineyard divided by soil type. The south block has less vigour and therefore requires different management to the north block. Our five pinot clones are planted on both sides of the vineyard, giving us 10 different clone/soil type combinations. We harvest these separately, and the wines are managed differently in the winery as they all contribute certain characteristics to the wine. We are slowly building up profiles from the different blocks to use in the future winemaking decisions. Every vintage has something to teach us.