Montreal (AFP) - Canopy Growth's share price plunged Friday after it released disappointing financial results, despite surging sales of cannabis -- eight months after recreational pot was legalized in Canada.

The company lost four times more than analysts had been expecting, even as production of the new cash crop jumped.

Canopy's share price fell nearly nine percent in New York to US$39.97 at midday, after the company late Thursday reported a loss of Can$323 million in the fourth quarter, far more than the Can$54 million loss in the same period last year

The company blamed higher costs for sales and marketing .

Excluding exceptional items, the quarterly loss was equivalent to Can$0.98 a share, four times higher than analysts had expected.

But sales were robust, up 313 percent to Can$94 million, for the quarter ending March 31.

And total cannabis production also rose to a whopping 14,469 kg and is forecast to double in the next quarter ending this month.

Sales should benefit from the opening of new stores by partners in key provinces of Ontario, Alberta and British Columbia, the company said.

In Canada, Canopy also operates a network of 23 stores under the "Tweed" and "Tokyo Smoke" brands in four provinces.

In April the company announced plans to purchase US pot grower and retailer Acreage, conditional on pot becoming "federally permissible" in the US, in a US$3.4 billion deal that it said would make it the "undisputed leader" in the US cannabis market.

Internationally, Canopy Growth has increased sales of cannabis for therapeutic use, particularly in Germany but also in Poland and the Czech Republic, where it has just opened.

Canopy also continues to invest in medical cannabis in Colombia, Spain, Lesotho, South Africa and Australia.