Two keys to Australian wine quality are the continent’s mostly hot and dry climate and its great number of technically proficient winemakers. Australia’s wine regions are spread across the southern rim of the country, generally close to the sea, from the Hunter Valley, just above Sydney on the east coast, across to the Margaret River, south of Perth on the west coast—a distance of roughly 2,000 miles. (The generic appellation South Eastern Australia is used to describe blended wines from virtually anywhere but Western Australia.) Making blanket statements about Australia’s weather in a given growing season would be almost like saying that Southern California and North Carolina experienced the same climatic conditions.

Even within fairly small areas conditions can vary dramatically according to ocean influence, altitude and type of soil. The often scorchingly hot Barossa Valley in South Australia, for example, can produce red Australian wines that approach vintage port in their dried-fruit flavors and alcoholic heft. But parts of the Clare Valley, less than 50 miles away, are significantly cooler. At the same time, though, Barossa benefits from a high percentage of old vines with deep root systems, which are more likely to be able to get water than younger vines in other regions, which rely heavily on irrigation and scarce water resources.

South Australia: This state dominates production in Australia, accounting for nearly half of all grapes crushed. McLaren Vale, south of Adelaide, enjoys a Mediterranean climate thanks to proximity to the ocean, with warm, dry summers and most of its precipitation concentrated in the winter months. With irrigation necessary but water scarce, the best wines come from low-yielding old vines with deep roots. McLaren Vale is best known for its fleshy, full-flavored Shirazes and Cabernets, but Grenache is on the upswing and there is also a good bit of mostly low-acid Chardonnay. The Adelaide Hills to the east of South Australia’s capital offer a coolish climate conducive to making vibrant Sauvignon Blanc and Chardonnay, as well as some finer and more elegant expressions of Merlot and Cabernet Franc. The Adelaide Plains, not surprisingly, is a hotter and drier area that produces rich, powerful reds.

Barossa Valley, Australia’s single largest producer of quality wines, makes some of the country’s richest, ripest, and most powerful reds, especially from oldvine plantings of Shiraz. Clare Valley, northwest of Barossa and distinctly cooler, yields more precise and sometimes more austere wines with typical minty undertones and more red than dark berry flavors. Just to the east of Barossa Valley but situated high above the valley floor, Eden Valley experiences considerably lower temperatures and higher rainfall. The rocky, well-drained soils here are best for Rieslings with firm acids, brisk citrus flavors, and considerable aging potential, as well as Chardonnays with better acidity than most. Shiraz is the most widely planted red variety, and is generally more aromatic, spicy, and fine-grained, as well as less weighty, than examples from Barossa.

Coonawarra is the best producing area within the mostly flat region midway between Melbourne and Adelaide known as the Limestone Coast, where cooling sea breezes bring down nighttime temperatures during the hot summer months. Coonawarra’s famous terra rossa soil (essentially, red loam over porous, quickly draining limestone, with traces of oxidized iron) is prized for producing intensely flavored, elegant wines with firm structure and great aging capacity, especially Cabernet Sauvignon. Padthaway, which also has some terra rossa soil, is best known for its Chardonnays.

Victoria: Heathcote, to the north of Melbourne and generally warm and dry, produces age-worthy Shiraz, with dense, often ultraripe berry fruit character. The very cool Mornington Peninsula south of the city of Melbourne produces fresh Chardonnay and Pinot Gris, as well as aromatically interesting Pinot Noir, but cool autumn weather normally arrives before Cabernet Sauvignon can ripen fully.

TheYarra Valley northeast of Melbourne, also reasonably cool and moist, produces a high percentage of Australia’s best Pinot Noirs, as well as some elegant, firmly structured examples of Cabernet Sauvignon, typically blended with other red Bordeaux varieties. The cooler climate and slow ripening of the grapes in Yarra Valley allow for wines with excellent flavor intensity and fine tannins.

New South Wales: Hunter Valley, a very warm region north of Sydney that’s often rather humid in summer and early fall, has long been the source of outstanding, long-lived Sémillon and juicy, earlier-maturing Chardonnay made in a modern and more oak-influenced style, typically with notes of tobacco and honeydew melon. Medium-weight, spicy and meaty Shiraz, often slow to mature in bottle, is also a specialty of Hunter Valley.

Western Australia: Situated on the extreme southwestern edge of the Australian land mass, the ocean-influenced Margaret River region benefits from a long growing season. Its Chardonnay is typically focused, crisp, and age worthy, while Cabernet Sauvignon has long been the favored red grape of the area, producing wines in a distinctly Bordeaux-like style. Shiraz has been growing in popularity, especially among winemakers and consumers who prefer a more precise Old- World style.

The cooler Great Southern region to its south and east is home to a more Germanic expression of Riesling than is usually found in Australia, plus spicy, peppery Shiraz with Rhône-like weight and complexity.

Tasmania: This large island south of the eastern mainland of Australia offers the most temperate growing conditions of all, with slow ripening of the fruit ideal for making vibrant Pinot Noir and Chardonnay, as well as aromatic white varieties like Riesling, Pinot Gris, and Gewürztraminer. Not surprisingly, Tasmania is widely seen as Australia’s best source of base material for sparkling wine. Plantings here are relatively tiny compared to South Australia, New South Wales, and Victoria but are increasing rapidly.