January 22, 2009 at 6:59 AM EST

SASKATOON — Potash Corp. of Saskatchewan said Thursday an ongoing demand for fertilizer helped triple its full-year earnings and pushed fourth-quarter profits to twice year-earlier levels.

The Saskatoon-based company recorded earnings of $3.5-billion or $11.01 per share for fiscal 2008,

Earnings were boosted by fourth-quarter profits of $788-million or $2.56 per share, up from year-earlier earnings of $376.8-million or $1.16 per share.

Potash reported a 2008 gross margin of $4.9-billion, up sharply from 2007 levels of $1.9-billion. Gross margin for the quarter ended Dec. 31 came to $873.1-million, 63 per cent higher than year-earlier levels.

'The unprecedented global economic challenges of the fourth quarter were a sharp contrast to the positive operating environment of the first three quarters of 2008,' Potash CEO Bill Doyle said.

Potash Corp. of Saskatchewan

Potash said its full-year results included a writedown of nitrogen and phosphate inventory values worth $88.9-million.

“The unprecedented global economic challenges of the fourth quarter were a sharp contrast to the positive operating environment of the first three quarters of 2008,” Potash chief executive officer Bill Doyle said in a statement.

“Our success over the course of the year demonstrated the resilience and adaptability of our company, as well as the effectiveness of our strategies in rapidly changing conditions. Potash, our core nutrient, holds unique advantages that enable us to deliver strong performance, even in a very difficult economic climate.”

Potash's earnings come a month after the company issued temporary layoff notices to 940 employees, who will be without work for at least eight weeks.

The company also cut its 2009 earnings guidance to $10.75 per share, down from an earlier forecast of $12 to $13 per share.