Big dry cuts SA grain harvest

South Australia's projected grain harvest is likely to be dramatically reduced due to persistent dry conditions across much of the state.

Primary Industries SA says the grain crop is estimated to come in at 6.2 million tonnes, worth about $1.8 billion after below-average rainfall in July and August.

That is about 23 per cent down on the 10-year average.

"Since the release of the last Crop and Pasture Report and a positive start to the season, many farmers were hoping for significant rain which sadly hasn't arrived," Primary Industries Minister Tim Whetstone said on Thursday.

"In a double blow, frosts occurred during August, with damage to heading and flowering crops, with some farmers deciding to cut the damaged crop for hay or using it as feed."

Mr Whetstone encouraged drought-affected farmers to access the support available.

"I acknowledge this is a very difficult season for many of our growers and I encourage them to access support if they need it," he said.