Vendors Display Marijuana Products at Washington Expo 2015-03-04

You wouldn't expect a marijuana expo in the U.S. capital, since it's still against federal law to possess the drug. And since it is still illegal to sell pot in the city, there was no marijuana at the trade show held this past weekend, at least none in sight, but there were small, startup businesses with products designed to grow the weed or consume it.

"I love marijuana so it's best to find out what everyone is starting to do for it," expo attendee Keith Carey said.

Visitors at the sold-out trade show ranged in age from their 20s to 70s. Many came because they were curious, now that Washington has legalized possessing small amounts of marijuana for personal use.

"I was just interested in what comes with this new legislation that passed, sort of, 'What are the things we can start looking into to take advantage of the new freedom we have?' "visitor David Jackson said.

On display were lighting systems and planters. Eric de Feo, co-founder of Roots Planter, said his seedling planter was designed for indoor vegetable gardens.

"We really didn't start getting traction with this product until it was suggested you can use this for cannabis," he said.

Visitor Rosina Memolo said she might have found the system that works for her. "I plan to plant my lettuce, my tomatoes, my cucumbers, if the bugs don't get them, and marijuana," she said.

In Washington, it's now legal to cultivate up to six marijuana plants at home. David DeGraff, owner of the Grow School in Colorado, said anyone can learn how to cultivate the weed through his online classes, "how to set up their grow room properly, how to water and fertilize, how to solve problems in the grow room that might occur."

Users who want to know more about the many strains of marijuana can turn to free apps from the online service Leafly. Co-founder Cy Scott said the most popular variety is called Blue Dream.

"It's a pretty readily available strain, and it's also one that doesn't put you to sleep like so many do, so people really like it," he said.

How can you know if your marijuana is safe to consume? Terron Gray of Uplifted Healing Services has a mobile machine for that purpose, and for a fee, he'll check your pot for potency, pesticides and fungicides.

"And I'll take my machine to whatever residence or wherever you want to be to test your cannabis," he said.

Chris Wrights' Maryland-based company, Scentless, found a new air-purification market for marijuana.

"We've designed filters for the indoor gardens and tents that will remove 100 percent of the odors so you can grow it discreetly," Wrights said.

And those looking for drug paraphernalia could find plenty at the expo.

After seeing all the products, visitor Katie Eye said she was considering a career change. "There are plenty of businesses ... a lot of marketing opportunities, sales for the future," she said.

She's not alone. Like others, she believes she can make a pot of money with legal pot.