Adelaide Hills Region
The Adelaide Hills winegrowing district is a 70km swathe of the South Mount Lofty Ranges stretching from Mount Pleasant in the north to Mount Compass in the south.
Historically grapes were grown very early in the settlement of the Adelaide Hills. The earliest record of South Australia's first commercial winemaking enterprise was John Barton Hack who established an acre of vines at his Echunga Springs property near Mount Barker in 1839 and produced his first wine in 1843. In 1844 a case of his wine was forwarded to Queen Victoria. The vineyard continued to operate until at least 1856. German immigrants also arrived in the Adelaide Hills and planted vines at Hahndorf and Lobethal around 1842.
The vine disease oidium, which first appeared in 1872 and spread rapidly, was particularly expensive to control. In 1876 when a crop of wine grapes brought between £9 and £12 per acre, Thomas Hardy put the annual cost of three applications of sulphur at more than £1 per acre.
The resurgence of viticulture in the Adelaide Hills came about in the 1970s, when the Verralls at Glenara established vineyards in 1971, and Petaluma in the late 1970s. Other producers such as Knappstein, Weaver and Henschke entered shortly after, followed by Cootes, Seppelt, Ashton Hills, Kuitpo Vineyards, Gumeracha Vineyards and others, and have proven that the Hills offers a diversity of microclimates to suit a range of wine styles from sparkling to premium quality table wine. There are currently more than 20 wine producers listed as members of the Adelaide Hills Wine Region.
The Adelaide Hills can be categorised into warmer and cooler subregions. The Piccadilly Valley is cooler than elsewhere in the Hills and quite humid, which has a unique effect on the vineyards. It has the lowest heat summation, and since it is located directly behind Mount Lofty, it often has a band of cloud or fog over the area while the rest of the hills is bathed in sunshine. Hence it seems particularly well suited to sparkling wine production.
Harvest dates for the different varieties suggest later ripening at Piccadilly than elsewhere in the Hills. There is a north to south trend with harvest dates from Mount Pleasant to Piccadilly, and a south to north trend from Kuitpo to Piccadilly. Thus the centre point for late maturity appears to lie in the Picadilly/Ashton area, which has the coolest temperatures, highest rainfall and highest altitudes of the South Mount Lofty Ranges.
The grapes for sparkling wine are being consistently picked at around 18°Brix with higher acid levels than elsewhere in the country. The Mount Lofty area has a lower heat summation than the Yarra, Coonawarra or Geelong and about the same as Drumborg.
In this region there is a variety of slopes. The warmest slopes facing north are capable of producing grapes of table wine composition; the coolest slopes suit sparkling wine.
Lenswood has for decades been known for the quality of its apples and since the early 1980s it has also become known as a premium winegrowing area. Warmer than Piccadilly Valley and with a greater heat summation, it has the ability to ripen early varieties in most years. The varieties which have proven to be the most successful are sauvignon blanc, riesling, pinot noir and merlot.
Ashton and Carey Gully lie somewhere between these other two areas in terms of climate and suitability to grape varieties.
Further north to Gumeracha and Mount Pleasant temperatures tend to become warmer - consistent with the corresponding decrease in altitude and rainfall and hence there is a tendency to earlier ripening and higher sugar levels.
However as the Adelaide Hills is mountainous and so diverse, the aspect and soil type can have a dramatic and major effect. The northern slopes are favoured to encourage earlier ripening, and well-drained soils decrease vigour. Unless vigour is controlled many other viticultural problems are created: dense canopies, shading, poor exposure, etc.
Gumeracha and in particular Mount Pleasant seem to be better suited to the later-ripening varieties such as cabernet sauvignon and riesling than the higher parts of the hills, and also most likely suited to shiraz.
Climate & Soils
The region may be classed as cool, moderately maritime, moderately sunny and moderately humid. The undulating and steep sloping terrain around Lenswood minimises frost risk and the altitude and protected sites reduce the chance of a heat wave during the summer. Harvest dates range from mid March to early April for pinot noir to the end of April to early May for riesling and merlot.
Annual rainfall lies between 700-1200mm. Soils vary considerably and include well-drained sandy loam with shale fragments overlying clay, weathered schists, skeletal quartzites, sandstones and podsols of varying fertility.