Three varieties take on an extra flavour dimension when grown in a warm climate. These are Shiraz, Mataro and Grenache. Indeed getting Mataro and Grenache ripe enough to make a wine of any standard is hard to impossible in cooler climates. All three were favoured for the high sugar content they develop when fully ripe and became the backbone of the red varieties used in fortified wines where colour and alcohol were required.
The move to table wines lifted Shiraz to a favoured status. Mataro was used in small amounts to blend into Shiraz and the role of Grenache was a puzzle though plantings were kept for high quality tawny ports. Slowly consumer support grew, and while we lost many old plantings to the 1980s vine pull scheme, some survived.
A blend of the three is becoming a status symbol of the Barossa Valley.