PORTLAND, Ore. (Reuters) - More than a thousand marijuana enthusiasts and entrepreneurs met in Oregon on Friday to swap samples, contacts and business tips in hopes of profiting from the state's new law allowing the recreational use of pot.

Licensed growers handed out free tastes, gardening experts displayed organic plant food and artists sold marijuana pipes to participants at the "Weed the People" event.

“Cannabis is a great opportunity for us," said D.J. King, a labor organizer with the United Food and Commercial Workers who wants to unionize workers at marijuana grow operations, distributors and retailers.

“There is a lot of money being made, and we want to be sure to spread it out,” she said.

Smoking marijuana recreationally became legal in Oregon on Wednesday. The law opens the way for shops to sell marijuana by next year.

Similar legalization initiatives have ushered in retail pot shops in Washington state and Colorado, reflecting a shifting landscape for a drug that remains illegal under federal law.

Alaska has voted to legalize marijuana and hopes for pot shops in 2016, while the District of Columbia has voted to allow recreational-use marijuana but not retail shops.

At "Weed the People," entrepreneur Joshua Waldman said he has a license to grow medical marijuana and attended the event to learn how to become a recreational grower.

“I want to be sure everything I do is legal,” Waldman said.

Under Oregon’s gradual approach to legalization, medical use has been authorized for decades.

Regulators will start accepting business license applications in January, with stores slated for next fall.

Some like Katy Hammond simply came for fun and for free samples.

"We want to be part of history in the making,” the 25-year-old Hammond said.

Driving while high remains illegal and pot cannot be taken out of state. Public smoking also remains illegal.

(Editing by Ellen Wulfhorst; Editing by Kim Coghill)