Many investors run hot and cold with marijuana stocks, to say the least. These days, the hot part of that equation seems to favor multi-state operators (MSOs), the companies that manage the dispensaries where consumers get their "legitimate" weed.

In this video from Motley Fool Live recorded on July 16, longtime Fool contributor Eric Volkman and healthcare and cannabis bureau chief Corinne Cardina briefly discuss one segment of the pot market that's far lower on the temperature scale for investors.

Corinne Cardina: How about picks-and-shovels, how are they doing?

Eric Volkman: Not particularly well. They have not been popular.

If we look at the two big pick-and-shovel plays, we're talking GrowGeneration (NASDAQ:GRWG), which is a hydroponics retailer that just can't stop acquiring assets, and Scotts Miracle-Gro (NYSE:SMG), which is a more traditional play that has gotten into marijuana over the last couple of years. People seem to be ignoring them. I don't necessarily think they should.

GrowGeneration is down. Again, year-to-date 1% while Scotts Miracle-Gro has slipped by 11%. I don't think it's fair.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.