In less than 40 years, Marlborough has gone from being an unknown, to New Zealand’s largest wine region, making up 75% of the country’s total wine production in 2011.
Variable soil types, a readily available underground water supply, relatively dry arid weather conditions and high sunshine hours, characterise the region.
Marlborough may not reach the extensive highs or lows of some other grape growing regions, (such as Central Otago) but it is renowned for its diurnal temperature variation. During the growing period it is common for daytime temperatures to reach mid 20s on a regular basis, with the diurnal shift being an average 11 degs. This allows the grapes to build the brix levels during the day, with the high level of fruit acids being retained during the cooler nights.
Long dry autumns also play a major role in the ensuing wines. Without the pressure of rain the fruit can generally stay on the vines longer, allowing flavours to ripen without sacrificing the acidity that delineates Marlborough wines. Those long fine autumn days also help prevent disease threat. (In most years anyway. There are always exceptions to the rule unfortunately.)
When you fly in to Marlborough, it becomes obvious how much the braided river ways impact on the province. They are what have created the soil types, throughout the region, over many thousands of years. As recently as 200 years ago, the plains were covered with many small tributaries of the Wairau River, resulting in deposits of alluvium and stone. Once those rivers began being stop banked and channelled, large tracts of flat land became suitable for farming, horticulture and later viticulture. Much of that land was covered with the remnants of the quantities of macerated rock, brought down from the hills centuries before via the river system. Marlborough is also heavily influenced by its fault lines with the Wairau, Awatere and Clarence faults being an extension of the Alpine Fault.
All have played a role in Marlborough’s geological formation.
The first of Marlborough’s modern vineyards was planted in 1973 in what is referred to as the Southern Valleys. The now famous Brancott Estate, Montana’s first vineyard, sits smack bang in the middle of this area.
It wasn’t long before people began looking at other parts of Marlborough that may well be suitable for vines. The Wairau Valley, a large tract of relatively flat land that borders the Wairau River and Wairau Fault line, was the second sub region to develop, in the late 70s. Covering a total area of just 20,000 hectares, this pocket of land is now covered in vines.
In 1985 the first vineyard was planted in the Awatere Valley, south of Blenheim, and separated from the Wairau by the distinctive Wither Hills. It took many years for the Awatere to take off, in terms of vines, but in the past 10 years, it has grown exponentially. To the point that the vineyard area of the Awatere Valley on its own, is now larger than Hawkes Bay.
Wine Marlborough, the representative body of the growers and winemakers of the region, has deemed these three valleys as the sub regions within the greater Marlborough area. But as is becoming more apparent as the years move forward, there are some very distinctive sub regions, within each of these valleys.
Home of the original vineyards, The Southern Valleys lie to the south of the Wairau Valley. This is an area within Marlborough that has not been as heavily affected by the river system over the millennia. It is slightly more rolling than the Wairau Plains and the soil variation is quite different. Created by a glacial outwash, it has significant amounts of silt and gravel, but also exhibits higher levels of clay than the other sub regions. Temperature wise, it is deemed cooler than the Wairau, and being closer to the hills, it is more prone to the cool air draining off them and settling for longer in the valley folds.
It is a drier sub region than the Wairau Valley in terms of rainfall, despite it being only a matter of a few kilometres to the south. The area has also suffered from a lack of water during its developmental stage, given it’s distance from the two major river ways, Wairau and Waihopai.
During the last big drought in the late 90s, people were having to hand water vines, with water delivered by tankers. Since then the Southern Valleys Irrigation Scheme has been in commission, ensuring there is a reasonable amount of water available when necessary.
The major varieties planted in The Southern Valleys are; Pinot Noir, (more and more on the gently sloping hills of the valley) Sauvignon Blanc and Chardonnay.
Because the sub region is slightly cooler than the Wairau Valley, there is a greater risk of frost, although hundreds of frost fans are helping to mitigate this threat. The season is also behind that of the Wairau Valley, in terms of harvest.
The white wines from this valley tend more towards the citrus/grapefruit flavours, with a degree of minerality from the clay. Pinot Noir tends to display rich aromas of red fruit.
Within the Southern Valleys; the known sub regions are; Brancott, Fairhall, Omaka, Taylor Pass and Ben Morven and Waihopai Valley.
As mentioned earlier this tract of land covers just 20,000 hectares, with a significant portion of that given over to viticulture. It is difficult to describe the soil types of this sub region, given in one small vineyard there can be more than a dozen different profiles. They can range from stony, gravel, alluvial former riverbed, to silt, loam and clay. What’s more the soils can range from being highly fertile, to extremely poor. Stones abound in parts of the valley, deposited by the braided rivers over the years. (Stoneleigh Wines took their name from the never ending array of stones within the original Corban’s vineyard.)
The closer to the hills of the North, the more rainfall this area experiences. It can be substantially more than the Southern Valleys and even more again than the Awatere. This along with the fact that the vineyards in this sub region sit above a massive aquifer, fed by the Wairau River, means there are not as many water issues facing growers in this sub region as there are in others. While the more fertile loam soils mean irrigation is often not necessary, it is almost mandatory on vineyards with stony conditions.
Temperature wise the Wairau Valley tends to be warmer than either the Southern or Awatere Valleys. It is generally the first of the sub regions to be harvested.
The major variety is understandably Sauvignon Blanc, with the Pinot Noir predominantly for sparkling with some table wine the second most planted, then Chardonnay.
More recently there has been a move towards other aromatic wines, such as Riesling, Pinot Gris, and Gewürztraminer. The wines from the Wairau Valley are described as being very fruit forward, with stone and tropical fruit flavours, particularly passion fruit and grapefruit characteristics in the Sauvignon Blanc.
Sub regions within the Wairau Valley are numerous. They include, Rapaura, Renwick, Rarangi, Conders Bend, Kaituna , Grovetown, Dillons Point and now the more extensively planted Upper Wairau, which is to the west of Blenheim, and follows the line of the Wairau River itself.
The Awatere Valley
Situated to the south of Blenheim, with the Wither Hills dividing it from the Wairau and Southern Valleys, the Awatere is the most recent of Marlborough’s sub regions to emerge. As mentioned the first vines were only planted back in 1985 by Vavasour Wines.
There were many in the Wairau Valley that believed the Awatere would never be a major player in the Marlborough wine arsenal. How wrong they have been proven. The Awatere is a not only a major player in terms of plantings, but also in fruit profiles. Wines from this sub region tend to be crisper, less tropical fruit (in terms of Sauvignon Blanc) and are often described as herbaceous, capsicum/bell pepper, minerally and flinty.
Towering over the Awatere Valley is Mount Tapuae-o-Uenuke, New Zealand’s highest peak, (outside of the Southern Alps.) Often tipped with snow, it is a clear indication of the potential for cool weather that assails this valley. It is renowned as being cooler, windier and drier than either of the other valleys, which means bud burst through to harvest is the latest of all three valleys.
The soil profile is also very different, being a mixture of alluvial gravel and wind borne loess, often with a diverse composition of stone materials.
With the majority of plantings being closer to the sea (than other valleys) the diurnal temperature is also less.
There are no large aquifers in the Awatere and all irrigation water has to come from the Awatere River, or storage dams. Given the strong winds the area is subjected to, irrigation is a necessity, not a luxury. The private Blind River Irrigation scheme, opened up large tracts of land and many growers have now built their own storage dams to cater for the ever likely potential drought.
But the lack of water also means crops are lighter and flavours tend to be more intense, helped by the long hanging time due to the later ripening.
Within the Awatere Valley there are many individual sub regions; Blind River, Seaview, Dashwood and Redwood Pass. There are also areas emerging south of the Awatere in the Ure Valley and Kekerungu, which are beginning to show real promise. ν