Dr. Greenthumb's

Dr. Greenthumb's is cannabis and lifestyle brand founded in 1998 by Louis Freese AKA B-Real, the lead rapper of the legendary hip-hop group Cypress Hill. Named after Cypress Hill's iconic 1998 counterculture anthem, the brand bridges music, culture, and cannabis cultivation and has grown into a highly structured retail and wholesale brand ecosystem.

The brand opened its first physical storefront in August 2018 in Sylmar, California, and has expanded across California (including Sacramento and La Mesa). Its flower lines and proprietary products are distributed across multiple states, including California, Washington, Florida, Michigan, and Arizona.

In 2022, the brand launched a structured flower line segmented into three distinct price tiers (Loyal, Legacy and Unapologetic) to serve different consumer budgets. The brand prioritizes "elite genetics" and local "craft" growers, vetting farms for cultural authenticity rather than pure corporate scale. One of that strains is, as example, Insane OG, B-Real's signature, high-potency Indica-dominant strain, testing between 25–32% THC. It serves as the flagship flavor profile of the brand's product lineup and is also available as seeds thanks to a partnership with the dutch seed bank Barney's Farm.

Beyond raw flower, the brand licenses its name for consumer smoking hardware.