North Canterbury and the Waipara Valley
A series on one of New Zealand's most interesting wine regions: part 2, physical characteristics

If you look at the Waipara Valley’s climate data, you’ll find that it is one of New Zealand’s coolest wine regions, with GDDs of around 1090 (by way of comparison, Marlborough is 1200, Martinborough is 1130 and Central Otago is 995). Springs are cool, but when summer kicks in it can be warm here. The autumns are long and settled.

The valley is protected from the easterly winds by the Teviotdale Hills. These easterly winds affect around 30% of summer days, and they are significant. (If the wind is from the northwest it is warm everywhere, including down in Christchurch, and if it's from the south, it's cold everywhere.) The result is that the valley is 1–2 degrees warmer than Christchurch. Average temperature in February is 17.7 °C, which is very similar to Nelson and Central Otago. The southern alps act as a rain shadow, and so rainfall here is quite low at 648 mm, with just 360 mm falling during the growing season of October to April.

There are three main soil types in the valley, which is reported as having the most diverse soils of any of New Zealand's wine regions.

• The first is the river terraces. The Waipara river, flowing on an old glacier bed, formed north facing terraces which a lot of the vineyards are planted on. It’s a bit like Martinborough, with a thin layer of wind-blown loess sitting over free draining gravels.

• Then there’s the valley floor, which has a deep layer of clay over gravels, with some limestone-derived clays in the eastern portion, and in the south gravelly loams over an alluvial subsoil.

• Finally, the hill slopes which are limestone-derived clays: clays layered with fragmented limestone.

[For more details, see this interesting soil map of the North Canterbury region, with the location of vineyards marked.]

Waikari, the newest development of the North Canterbury wine region, northwest of the Waipara Valley, shares the protection from the easterlies and has a similar sort of climate. The big difference here is that there’s quite a bit of limestone in the soils here.

A soil pit at Pyramid Valley, Waikari

[The North Canterbury vineyard soils are the subject of academic study by Dr Roland Harrison and Dr Philip Tonkin at Lincoln University. I'm trying to find out more details about the results.]

Currently, there are 1462 hectares of vineyards in North Canterbury, up from 853 in 2005, but shy of the peak of 1809 in 2010 (data from NZ Winegrowers annual report 2014).

Main grape varieties