RIVERLAND citrus was one commodity affected by a series of frost across the state last week, with early growth of some Mid North broadacre crops also hindered.
Citrus SA chair and Sunlands citrus grower Mark Doecke said he had sustained some minor frost damage to late-maturing varieties, but strategies such as turning on overhead watering systems during the night and applying molasses to fruit had helped minimise losses.
"With some of our later varieties we put overhead water on during the night because you can create an igloo over the tree," he said.
"The ice temperature is zero, whereas the air temperature is down to minus four or minus five degrees.
"At zero they get minimal damage, but if they are exposed to minus four or minus five they'll just cook."
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Mr Doecke said his later-maturing citrus varieties, including later mandarins and later navels, were more susceptible to damage due to their lower sugar content at the time of the frost event.
"Varieties that are ready to pick are better off because they're sugared up and more sugar lowers the freezing point," he said.
Harvest started last week for Mr Doecke.
He said picking of their earlier-maturing varieties like mid-season navels had begun, with fruit quality and quantity pleasing to-date.
"It was a pretty horrendous summer - we had some rain through the growing season, but we had those mid to high 40-degree temperatures too - so considering that we're doing pretty well," he said.
Salter Springs agronomist, Craig Davis, said frost-prone areas in the Mid North suffered last week, with some growers reporting up to eight frosts in the series.
He said the frosts were quite severe, both in temperature and longevity.
"They have definitely slowed crop growth and coupled with some areas starting to dry out a bit, it has impacted on establishment and early growth of later-sown crops," he said.
"The damage is unlikely to be sustained though because it's only vegetative."
Mr Davis said some northern cropping regions had dried off in recent weeks due to missing out on coastal rains.
That, combined with frosts, meant good soaking rains were needed for crops to get going again, he said.
