. >> reporter: paul henderson, formly with goldman sachs, n c.e.o. of grupo flor, which owns two dispenries and will open 18 more within a year. >> we'll do around, now, about 1.3 million a month in sales. >> reporter: right here? >> this store alone, yeah. >> reporter: and grupo flor isn't just retail. in a few years, the firm's become one of california's largest cannabis companies: from retail, to cultivation... to manufacturing... and distribution. cofounder mikeitar had been in commercial real estate. >> i just happened to stumble across cannabis and saw how lucrative it was and realized we should get in the business. w >> reportee you a user? >> no. i didn't see the difference, unfortunately, between heroin and marijuana. >> reporter: well, he soon did. by 2016, when californians voted to legalize recreational adult marijuana use, bitar and partners had already snapped up one and a half million square feet of greenhouse space-- lying fallow since the cut flower hbusiness emigrated to so america. they'd grow caabis instead. there might not be a l