Queensland farmers have welcomed special loans and grants from the government in the wake of devastating floods.

Under the "Category D" assistance package, eligible farmers can access loans of up to $650,000, of which $50,000 will not have to be repaid.

Recipients won't have to pay any interest on the loan for two years.

Farmers' organisations have welcomed the package, with the canegrowers' body calling it "a godsend".

"Category D will be the thing that keeps some canegrowers in the game," Canegrowers chief executive Steve Greenwood said.

The Queensland Dairy Farmers Organisation says the package will be vital for many producers.

However, the organisation's president Brian Tessmann warned some might be wary of taking on more debt.

"Coming so soon after the 2010-2011 floods and with the ongoing milk price war, the recovery from this flood will be especially difficult," he said.

Widespread flooding caused by former tropical cyclone Oswald last month devastated many of the state's primary industries.

The citrus industry's losses equalled an estimated $100 million; the dairy industry's losses came to about $40 million.

Half the state's dairy and pork farms were affected, and cotton and cane growers were also hit hard.