The US plantings estimates which shocked crop markets on Wednesday represent a fillip to fertilizer groups in forecasting higher plantings of nutrient-hungry corn, Mosaic Co said.

The company forecast a rise of roughly 30% in its average phosphate selling prices for the March-to-May period, noting that inventories held by North American producers "remain lean and well below the three-year average".

Potash prices would stay at 5-365 a tonne, free on board, representing an end to their drawn-out correction, with sales volumes set to triple from those a year before.

The forecasts reflected hopes for a "strong American spring season", Mosaic said, flagging Wednesday's US Department of Agriculture estimates for domestic sowings.

'Positive shift' 

"The report� indicated that US farmers intend to plant the same total acreage as a year ago, but then plan to plant more corn soybeans and cotton and less wheat and other small grains than last year," the company said.

"This shift is positive for crop nutrient demand prospects this spring."

Fertilizer costs for corn can be, at potentially an acre, some 40% greater than those for wheat, according to Purdue University estimates.

Furthermore, many farm commodities were trading at relatively high levels, generating "profitable farm returns throughout much of the world," Mosaic said, adding that the fate of Chicago's weakened corn and soybean prices would yet depend on harvest yields.

Results fall short

However, the group noted a limit to buyers' appetites, noting that customers had met the last quarter's 17% rise in phosphate costs, "with some caution".

And the comments came as the company unveiled earnings for the December-to-February period below Wall Street forecasts if, at 2.6m, more than three times higher than a year before.

Per share, earnings came in at .50, compared with analysts' expectations of .61.

Separately, the group revealed it was to pay Brazil's Vale 5m for a stake in a Peruvian phosphate mine the South American group is developing, backed by Japan's Mitsui.

Mosaic shares closed 4.0% lower at .33 in New York.