Location and boundaries
Margaret River is located in the south-west of Australia within the South West Australia GI. The geographical designation covers around 2,137 square kilometres and stretches as a narrow coastal strip between Cape Naturaliste and Cape Leeuwin. To the west, the region borders the Indian Ocean, and to the south, the Southern Ocean. The legal GI boundary includes the parts of the Shires of Busselton and Augusta Margaret River located west of longitude 115°18′E.
Climate and soils
The Mediterranean climate is characterised by rainy winters, dry summers and the strong maritime influence of both oceans. Cooling sea breezes in the afternoon ensure, during the growing season, a comparatively low daily variation in temperature and an even accumulation of warmth. Average annual rainfall is about 1,100 millimetres, and the average January temperature is 20.6 °C. The vineyard areas are between 0 and 234 metres above sea level.
The Dunsborough Fault separates western and eastern geological areas. In the west, the Leeuwin Complex and lateritic formations shape the area, while the east has sandy soils made up of weathered sedimentary rock. Important soil groups include ironstone-containing Forest-Grove gravel soils and sandy Mungite-Duplex soils. The regional bedrock comprises granite and gneiss, which are dated to around 1,130 to 1,600 million years ago.
Grape varieties and winemaking
The most important grape varieties include Cabernet Sauvignon, Chardonnay, Sauvignon Blanc and Semillon. In addition, among others, Shiraz, Merlot, Chenin Blanc, Malbec and Tempranillo are grown; overall, more than 40 varieties are represented in the region. The Gingin clone, originating in Western Australia, is widely used in the Chardonnay vineyards and produces small bunches with berries of varying sizes and comparatively low yields.
Cabernet Sauvignon is usually produced as a medium- to full-bodied red wine and is partially blended with Merlot, Malbec or Petit Verdot. Chardonnay appears concentrated yet well balanced, with natural acidity and texture, which can be created, among other things, through fermentation in French oak barrels and yeast ageing. Sauvignon Blanc and Semillon are often combined into dry white wine cuvées; the range of styles extends from fruit-led wines to more structured examples suitable for longer ageing. Shiraz is described predominantly as medium-strength, aromatic and fruit-driven.
Development and legal status
In 1955, the oenologist and viticulture researcher Harold Olmo recommended south-west Western Australia for wine-growing. Investigations by John Gladstones from 1965 and 1966 identified Margaret River and adjacent areas as suitable. The first modern commercial winery established Cabernet Sauvignon and Malbec plantings in 1967 at Vasse Felix; Moss Wood followed in 1969. The first Chardonnay plantings were made in 1976 at Leeuwin Estate, Cullen Wines, Ashbrook Estate and Moss Wood.
The Australian geographical indication “Margaret River” was entered into the register of protected names on 30 October 1996. Statements concerning vintage, grape variety and geographical indication are optional under the Australian labelling regulations; where they are used, they must comply with the Australian blending rules and be supported by verifiable records.
