The Canadian company sold 636,000 tonnes of wholesale potash in the first quarter ended March 31 at an average of $208 per tonne, compared with 456,000 tonnes at $199 per tonne a year earlier.
Agrium's retail sales fell 2.2 percent to $2.24 billion. Wholesale sales of nitrogen, potash and phosphate were up 4 percent at $675 million.
The company's net loss attributable to shareholders was $11 million, or 8 cents per share, compared with a profit of $2 million, or 2 cents per share, a year earlier.
On an adjusted basis, it lost 7 cents per share, while analysts on average had expected a loss of 8 cents, according to Thomson Reuters I/B/E/S.
Last week, Potash Corp reported a bigger-than-expected rise in its first-quarter profit.
Reporting by Ahmed Farhatha in Bengaluru and Rod Nickel in Winnipeg, Manitoba; Editing by Sriraj Kalluvila