The extent of damage from a recent cold snap is becoming evident in the Barossa Valley.
Adrian Hoffmann is a grower at Ebenezer and says some of his neighbours have lost about 70 per cent of their wine grape crop because of cold weather.
He said it was still the first month of the growing season and the vines were fragile and vulnerable to weather damage.
"The frost most probably took out about a third of our area," he said.
"Yet to be known is the amount of cold damage that will be done to a lot of the young bunches that were sitting there.
"So even looking at the crop that's there now, you just don't know how damage is going to be done and we'll have to wait to fruit set to find out."
© ABC 2012
14:30 EST The Bureau of Meteorology has revised down its prediction of an El Nino weather event developing later this year.