Regional info.

While the Adelaide Hills region has been a wine growing area since the late 19th century, it more-or-less stopped producing and was only rediscovered as a good place too grow grapes as recently as 1978. At this time there were zero hectares of vines, and in 1990 Brian Croser was one of the two pioneers to have vineyards in the Piccadilly Valley. By 1999 there were 1982 ha, and by 2004 this had grown substantially to 3338 ha.

Adelaide Hills is actually quite a diverse region. It's thought of as cool climate, but some bits can get reasonably warm. Here are some figures, for what they are worth:

Piccadilly Valley is the coolest viticultural region in South Australia. Tucked in behind Mt Lofty, the Piccadilly Valley is a jigsaw of slopes and sub-valleys with an underlying geology up to 1,800 million years old. Planted on relatively steep north and east facing slopes, the vines receive the full benefit of the warming early mornings and heat from the sun traversing the northern sky. Piccadilly has 1177 degree days (a measure of heat summation during the growing season) and 1.4 m annual rainfall (the only red that will ripen here is Pinot Noir);

Lenswood has 1300 degree days and 1 m annual rainfall;

Mount Barker had 1413 degree days and 766 mm annual rainfall. The sandy loam slopes of Mount Barker are ideal for Viognier and Shiraz being far enough from the coast to produce a strong day to night temperature differential. The soils of Mount Barker are formed from the underlying micaceous granitic schist geology and are ideal for vigorous Shiraz and its white partner Viognier, producing ripe but elegantly structured wines.

By way of comparison, Coonawarra is 1444, Clare is 1737 (but has cold nights). Blenheim in New Zealand has 1101 degree days.

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