It is a good time to be invested in Canada-based pot companies.

Shares of Tilray Inc. (TLRY) - Get Report gained 21.8%, Cronos Group Inc. (CRON) - Get Report rose 21%, while Canopy Growth Corp. (CGC) - Get Report rose 2.8% Monday, August 27.

Those stocks are moving on news that U.K. brewer Diageo Plc (DEO) - Get Report , which makes Guinness beer, is holding discussions with at least three Canadian cannabis companies on a collaborative deal.

Diageo's interest comes at an important time for pot stocks in Canada as the legalization of recreational marijuana is set to take effect on Oct 17.

Diageo isn't the first alcohol company to attempt to get in on the cannabis revolution.

Earlier this month, Constellation Brands Inc. (STZ) - Get Report announced it was investing another $4 billion into Canopy Growth, boosting its stake in the company to 38% from 9.9%.

In the U.S. only nine states and the District of Columbia have legalized cannabis. So while the Canadian cannabis economy blooms the growth opportunities in the U.S. remain some years away.