Wet weather across British Columbia is threatening profit margins for producers of one of the province's largest — although illegal — cash crops — outdoor marijuana.

B.C. has endured weeks of unseasonable drizzle and grey skies this spring with temperatures touching record lows in the months of May and June, and growers are worried about mildew killing the seedlings.

Marc Emery, a marijuana advocate whom some media have dubbed the "Prince of Pot," said growers are worried their annual crop worth up to an estimated billion dollars may be rotting in the ground.

"They're all very nervous right now," Emery told the CBC on Tuesday.

"If this were interrupted by one or two days of sun and warm weather it would reverse all that. But because you have an accumulation of days — over three and especially up to five — that are cold and rainy, you'll probably lose most of the plants that have been put out there before now," said Emery.

But Nelson City Police Insp. Henry Paivarinta said the possibility of seeing less pot on the street won't make his job any easier.

"I don't think the weather really changes it a whole lot," Paivarinta said. "Obviously, the demand will still be there. If the supply is down, well, the price will simply be up."

That could mean better profits for those who grow marijuana indoors, away from Mother Nature's unseasonable conditions.

The economic value of B.C.'s illegal marijuana industry is difficult to determine, but over the years experts have estimated it exceeds a billion dollars a year.