G-13 by Unknown or Legendary
There isn't a strain surrounded by more urban myth than the legendary G-13. For decades, the story has been that it was a super-indica bred by the U.S. government—often whispered to be a CIA or FBI project at the University of Mississippi—before a rogue technician smuggled a single cutting out of a high-security facility known as "Greenhouse 13." While the government origin story is almost certainly a myth cooked up to build hype, what we do know is that a grower named Sandy Weinstein obtained the cut and passed it to Nevil Schoenmakers, making it a foundational piece of cannabis history.
Stripping away the folklore, the actual plant is an absolute powerhouse. G-13 is a pure, broadleaf Afghanica-style beast that grows short, squat, and wildly bushy. She produces dense, rock-hard buds that look like little green golf balls absolutely caked in sticky resin. Back in the day, the potency was considered untouchable, delivering a heavy, narcotic body blow that would sit even the most seasoned smokers right down. The flavor is straight old-school funk: deep, raw earth, pine, and a woody spice.
You literally cannot talk about modern indica breeding without acknowledging the impact of G-13. Even if the feds never touched it, underground breeders used it as a cornerstone to build the heavy hitters we smoke today. Crosses like G13 Haze and the legendary 88 G13 Hashplant are absolute staples in the seed game. Forum veterans still chase cuts that echo that raw, original power, knowing that true G-13 genetics are the backbone of serious hash plants.
🏆 Legendary Foundation Strain
This is one of the most influential cannabis varieties in history. G-13 has been used to breed 95 documented descendant strains in our database, making it a cornerstone of modern genetics.
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🧬 Explore the family: Indica · Electric Lemon G · Satin · G Force · JustFeminized.com - G13 Skunk · SoCal Lemon Diesel · Dixie Chicken · XJ-13 · Tangerine G13
Ancestry Pedigree
Original Strains
Growing G-13: what to expect
As an indica-leaning plant, expect a modest stretch after the flip (roughly 50–100%) and dense bud structure — which makes late-flower humidity discipline the main risk: keep RH in the 40s once buds fatten to stay ahead of mold. Growers familiar with Indica will recognize much of its behavior. Whatever the listing says, the cut in YOUR tent is the ground truth: log feedings, readings, and photos, and let the trends — not the label — drive decisions.
G-13 FAQ
Is G-13 an indica or a sativa?
G-13 is listed as indica.
What are the parents of G-13?
G-13 was bred from Indica by Unknown or Legendary.
What environment does G-13 like?
Standard cannabis bands work well: VPD 0.8–1.1 kPa in veg and 1.0–1.4 kPa in flower, with humidity stepping down from 65–75% as a seedling to 40–50% in late flower. See the stage-by-stage table on this page.
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