An historic opera house in Denver - once the site of a Democratic national convention - hosted more than 1300 people on Wednesday for the Women Grow Leadership Summit. This is the largest networking group for cannabis businesses, with more than 35 city chapters ranging from California to Florida, and even to Canada.

The for-profit networking group started here in Denver in 2014. As the first state to legalize and regulate recreational cannabis, Colorado has become the epicentre for canna business, not just businesses that "touch the plant" but ancillary businesses, too.

"Strength in numbers," Alicia Syrett, founder and CEO of Pantegrion Capital told the audience that is predominantly women, but sprinkled with men.

It's called Women Grow, but the room is filled with people from many different industries. Lawyers, heating and ventilation experts, edible chefs, security companies, marketers and more are madly exchanging business cards with one another during short breaks.

Attendees were here for a day full of networking and TED-style talks, meant to motivate this room into action with topics ranging from lab testing and compliance, to building a brand and choosing the right employees for a medical dispensary.

This may be the only place where Jeanne Sullivan, a venture capitalist from New York City, can dress like Wonder Woman to give entrepreneurs tips on how to woo investors and not get burned by bad ones.

Melissa Etheridge: get ready for a paradigm shift

Keynote speaker and musician Melissa Etheridge shared her personal journey with cannabis and told the audience that there is a paradigm shift happening.

The breast cancer survivor sees cannabis as the leader in a larger national and international conversation about health. And she called on people to take the energy used in efforts to legalize at the state level to lobby the federal government to change the laws.

"You mention cannabis to anyone on Wall Street and they say 'oh yeah'," she said with a smile. "They know these things. There's not going to be an 'us and them' soon. We are all affected by disease."

But while many in this room are already up and running in cannabis ventures, many are people who aren't even in the cannabis industry…yet.

Women see opportunities in the industry

Rebecca McConnell is from Wisconsin and Megan Bigalke lives just across the border in Illinois. The two friends are starting the Milwaukee chapter of Women Grow.

While the two live seven minutes away from each other, only one of them can access medical marijuana.

"Coming here I wanted to learn more, meet people, see how other people have done it and get inspired," said McConnell, who is currently a product manager at Walgreens.

"It's only a matter of time [before legalization], it's a business opportunity and getting in from the ground up," said Bigalke, who works as a real estate agent.

Bigalke dreams of starting an edible company, while McConnell wants to be a grower.

"We need more like-minded business people behind this movement instead of just looking like a hippie on the side of the road with a sign," said Bigalke.

Deb Irvine Anderson is covering the Women Grow conference for Civilized. E-mail her at [email protected]