Dianthus barbatus - a native of Europe and a common, if somewhat old fashioned plant in Australian gardens.
I have always known him as "Sweet William".
Apparently he was named so after William of Marlborough, Duke of Cumberland. The Duke led the English to victory at the battle of Culloden. He wasn't that sweet really and was extremely brutal towards the kings' enemies, the Irish and the Scots. Not surprisingly in Ireland and Scotland this dianthus is sometimes referred to as 'Stinking Billy'.
Is it a wisteria?