(Recasts with stock jump, cost-cutting)
By Rod Nickel and John Benny
Oct 31 (Reuters) - U.S. fertilizer company Mosaic Co on Tuesday posted bigger-than-expected profit on higher prices, and slashed costs to ride out an agriculture slump, sparking a 9 percent jump in its shares in early trade.
Mosaic, the world's largest producer of finished phosphate products, cut its dividend 83 percent, idled a Florida phosphate plant and said it would focus on repaying debt after it completes a $2.5-billion purchase late this year of Brazil fertilizer facilities from Vale SA.
Prices of phosphate and potash fertilizer, Mosaic's two main products, have risen year over year but still hover near multi-year lows due to excessive global capacity and weak crop prices.
"We are taking actions to make this company as competitive as it can be in any business environment," said Chief Executive Joc O'Rourke on a call with analysts.
The company's results may reassure investors that downside in the fertilizer industry is limited, offset partially by weak guidance for the current quarter, said BMO analyst Joel Jackson.
The stock was up 8.58 percent at $22.64 after hitting a three-month high in opening trade.
Mosaic will idle for at least a year its Plant City, Florida facility, which can produce up to 2 million tonnes of finished phosphate products annually, because it is among the company's costliest plants to operate, O'Rourke said.
Mosaic said fourth-quarter sales for phosphates are expected to range from 2.3 million to 2.6 million tonnes, compared to 2.5 million tonnes last year.
Potash sales will range from 1.9 million to 2.2 million tonnes for the fourth quarter, compared to 2 million tonnes last year, it said.
Operating earnings in the third quarter rose $70 million, despite a $26 million hit in its phosphates business from Hurricane Irma.
Mosaic sold diammonium phosphate at an average price of $329 per tonne, up from $326 a year earlier. Its average potash selling price was $182, up nearly 14 percent from last year.
Net earnings rose to $227 million, or 65 cents per share, in the third quarter, from $39.2 million, or 11 cents per share, a year earlier.
Excluding items, the company earned 43 cents per share, beating analysts' estimates of 18 cents, according to Thomson Reuters I/B/E/S.
Sales rose to $2 billion from $1.95 billion. (Reporting by John Benny in Bengaluru and Rod Nickel in Winnipeg, Manitoba; Editing by Bernard Orr and Phil Berlowitz)