If you're thinking of rolling your own cannabis play now that 19 states and DC have legalized recreational weed (and twice as many say medical weed is okay), think again.

A pure-play investor in retail weed dispensaries and purpose-built industrial cultivation facilities—what, you thought this stuff came from Yasgur's farm?—delivered a buzz kill of a message at GlobeSt.'s annual Net Lease Spring conference in NYC this week: now is the time to keep your powder dry.

According to Anthony Coniglio, CEO of New Canaan, CT-based NewLake Capital Partners—dude, you need to put "no free samples" on your biz card—that weed dispensary play you got high on last night with visions of $600 per SF pricing, cap rates as high as 14% and 20-year leases with 3% annual bong hits may have you waking up tomorrow morning with a $75 per SF "alternative investment."