Wine makers served more challenges

Temperatures across the state reached record highs up to 44.7 degrees during the first weekend of the month and two weeks later new records were set as the skies opened dropping up to 100 millimeters of rain in some areas.     

Adelaide University Oenology professor Denis Taylor said red varieties were the most at risk as grapes for sparkling and whites had already been harvested.     

A longer than normal flowering season meant grapes were ripening at different stages and could not be harvested in one swoop.

Professor Taylor said Shiraz grapes were still on the vine when the rain fell on February 14 and 15.

"With the water the question is whether mould will become an issue or whether the grapes will burst. It is a matter of wait and see," he said.

"We had a lot of summer rain a couple of years ago which ruined a lot of crops."

The Barossa was the worse hit of the wine regions with 98mm falling over the two days of storm weather.

Stacey Morrison from McGuigan Wines in the Barossa said the rain would slow down all parts of the wine making process.

"It has already been a challenging year," she said.

"Flowering was long and it has been a light tonnage and yields were small. Rain changes the taste of the fruit."

Ms Morrison said the challenging season would sort the good winemakers from the average.

"I think the rain will challenge the winemakers themselves," she said.

"This year will be a year about the winemaking – and those who know what they are doing will stand out from the rest."

The state's second largest wine growing region, Langhorne Creek, was not as badly drenched by the rain as the Barossa region but there was still concern for their vintage.

Robbie Potts from Bleasdale winery said the vines needed to dry out for the fruit to ripen nicely.

"That is working on an inch of rain," he said.

"I think the heat has done more damage for us so far."