The volume of rural exports surged 18.3 per cent in seasonally adjusted terms in the three months to the end of March, as the slump in demand for coal and minerals freed up ports and ships for farm produce.

"There were some pretty good harvests coming out of last year and some of the shipping capacity would have become available for rural exports," Rabobank senior analyst Wayne Gordon has told The Australian Financial Review.

"Largely, net exports is what kept us out of a technical recession and rural exports performed well."

Even though global prices for farm commodities have dropped during the financial crisis, the overall value of farm exports rose 4 per cent in the March quarter, thanks to the big increase in volumes.