A crew of Canadians are putting their cannabis cultivation expertise to the test this summer by competing in the 4 Plants Cup, a homegrown contest to see who can raise the stickiest homegrown icky in the land.

The idea for the challenge grew out of a series of Twitter conversations among Canadian weed-lovers, according to Jamie Shaw, one of the organizers of the volunteer-run competition.

"The overarching thing, I think, is we want to educate people about growing cannabis, and what better way to do it than show people how to do that, and how different people do it, and different methods that they have," she says.

Any Canadian adult can register to compete, as long as they follow all relevant federal, provincial and local laws on cannabis cultivation. (That unfortunately excludes Quebecers and Manitobans without a licence to grow medical cannabis.)

The competition is split into two tiers — amateur and professional growers — with four categories of cannabis per tier (indoor, outdoor, medical and rosin). Twenty-eight growers will be permitted to register in each category until June 18, and slots are already filling up.

At the end of the growing season this fall, each competitor will send the organizers a 28-gram sample of their crop. Those samples will be inspected and screened for safety, then anonymized and sent back to multiple competitors for blind testing and scoring. (Any cannabis that's deemed potentially unsafe to use will be disqualified.)

Aside from bragging rights, prizes for the winning growers remain to be determined.

Competitors will keep detailed "grow journals" documenting their gardening methods, which will be also considered during the judging phase. They'll also be asked to share pictures of their gardens, which will help ensure that the cannabis being judged was actually grown by the competitor in question.

But at the end of the day, the 4 Cup Plants will rely in part on the honour system to make sure everyone's playing by the rules. Jamie Shaw describes that personal integrity as something that's "an inherent trait of people that were using cannabis during prohibition.

"You often hear about all the distrust, but there has to be a lot of trust for somebody to invite you into (their) home and sell you some cannabis that's totally illegal," says Shaw.

Even though Canada's legal cannabis market is dominated by for-profit companies, Shaw suggests the 4 Plants Cup shows there's still room for homegrown cannabis culture.

"Grassroots efforts aren't going anywhere," she says.

"So while people complain about the commercialization of cannabis, there are a lot of us that are trying to make sure that it stays sort of community-oriented, and the education keeps getting shared."