Agrium lifted its estimate for profits in the latest quarter, and forecast a "strong" spring for fertilizer use, amid a fresh front in the battle with activist investor Jana, which is attempting to break up the nutrient group.

Agrium said that its earnings for the October-to-December quarter would come in "slightly above" $2.00 per share - beating the $1.50-1.90 a share it had previously guided to.

The estimate is also ahead of the $1.70 a share which analysts have pencilled in.

Mike Wilson, the Agrium chief executive, said that the upgrade "is due to a very strong finish to the fall application season" at its North American retail operations, reflecting an extended autumn season for fieldwork, and "continued strength in grain and oilseed prices".

"Going forward, continued strength in crop prices and low global grain inventories are anticipated to support a strong spring application season in 2013," Mr Wilson said.

Shares up 

The upgrade comes ahead of an investor day on Monday which some investors had anticipated may herald upbeat news on the company's performance, coming in the face of Jana's attempt to split up the company.

Agrium shares ended on Wednesday at four-year closing highs of Can$110.65 in Toronto, and of $110.88 in New York.

RBC on Tuesday raised to $120, from $115, its target for Agrium's New York-listed shares, on an "outperform" rating, citing bright prospects for Alberta-based group.

"We think 2013 will be a very good year for Agrium," RBC analyst Adam Schatzker said.

"With high crop prices, we expect North American farmers will again seek to maximise yields and acreage – all of which will be very positive for Agrium's retail and nitrogen operations."

'Alternate universe'

The statement also comes as Jana - a New York-based hedge fund which is Agrium's biggest investor, with a 6% stake - is attempting to win other shareholders to support its campaign for the group to be split between its retail and wholesale divisions.

Jana, which has put up five candidates for Agrium's 11-member board, is undertaking a tour of Canadian investors which account for an estimated one-third of the fertilizer group's shares.

"Agrium's board has been living in an alternate universe where shareholders have no desire to explore the many ways we've identified to unlock value," Barry Rosenstein, Jana managing partner, said earlier this week.

Agrium has said that holding operations in both retail and wholesale sectors helps to stabilise its profits.

It has also handed cash to investors by raising its dividend and undertaking a share buyback.