G13 Haze Strain

Strain Quick Reference

Genetics: Howard Marks, Mr. Nice Seed Bank & the G13 Legend

G13 Haze was created by Mr. Nice Seed Bank, co-founded by Howard Marks — the Welsh cannabis smuggler whose 1996 memoir Mr. Nice became a cult classic — alongside master breeder Shantibaba (Jaime) and the legendary Neville Schoenmakers, one of the pioneers of commercial cannabis seed breeding. The company name honors Howard Marks’ most famous alias, used throughout his smuggling career documented in the memoir.

The G13 Legend: Fact vs. Fiction

The G13 mythology is one of cannabis culture’s most enduring stories. According to the legend, the US government cultivated ultra-potent cannabis strains at the University of Mississippi in the 1960s and 1970s as part of classified research programs. The story continues that a technician smuggled out a cutting of the most potent phenotype — labeled Government Indica #13, or “G13” — which then circulated through the underground cannabis breeding community.

The verdict: This is almost certainly cannabis mythology. No documented evidence of a classified US government super-strain program at UMiss has ever been published. The University of Mississippi did (and does) grow cannabis for DEA research, but the idea of cultivating “super-indica” phenotypes and losing one to the black market has no verifiable basis. The G13 genetics used by Mr. Nice Seed Bank are real cannabis genetics — an elite indica with excellent characteristics — but the origin story should be treated as compelling folklore, not verified history. The legend does not diminish the quality of the strain itself.

Haze: The Other Half

The Haze parent brings sativa dominance, long flowering time, and a complex aromatic profile. Original Haze genetics trace to a cross of Colombian, Mexican, Thai, and South Indian landraces developed in California in the early 1970s. Haze remains the foundational sativa genetics in dozens of award-winning hybrids. In G13 Haze, the Haze component lifts the indica heaviness of G13 into a daytime-functional, mentally engaging experience.

Terpene Profile

Terpinolene is the defining terpene of classic Haze genetics and is relatively rare in modern hybrids, which tend to favor myrcene-heavy profiles. Its presence in G13 Haze gives the strain a distinctive freshness — pine and citrus-floral notes that lift above the earthy base. Terpinolene is also associated with uplifting, energizing effects, consistent with the strain’s daytime functionality.

Effects: Three-Phase Experience

Phase 1 — Mental Clarity & Uplift (0–20 minutes)

G13 Haze opens with a clean, sativa-style cerebral activation. The Haze genetics produce a clear-headed energy rather than the racing, anxious intensity some pure sativas trigger. Users report heightened focus, creative ideation, and a pleasant mood elevation. The onset is smooth and functional — suitable for daytime productivity from the first few minutes.

Phase 2 — Balanced High with Body Component (20–90 minutes)

As the high reaches its peak, the G13 indica heritage begins contributing a gentle body warmth. The mental clarity of the Haze is still fully present, but a comfortable physical ease settles underneath, making extended activity — creative work, conversation, light exercise — feel effortless and enjoyable. This is the window that distinguishes G13 Haze from pure sativas and pure indicas: the balanced overlap is the strain’s signature.

Phase 3 — Relaxed Calm (90 minutes onwards)

The comedown is gradual and pleasant. Mental activity slows naturally and the body relaxation becomes more pronounced without tipping into couch-lock. Most consumers remain functional in this phase, making G13 Haze a rare strain that maintains usefulness from onset through tail.

Cannabis Cup History & Awards

G13 Haze has won multiple High Times Cannabis Cup awards for Mr. Nice Seed Bank, cementing its reputation as one of the finest examples of the Haze hybrid format. These wins reflect the strain’s genetic stability, consistent terpene expression, and the difficulty of maintaining true Haze-hybrid quality at commercial scale — achievements that established Mr. Nice Seed Bank as a top-tier genetics house during the Amsterdam seed bank era of the 1990s and 2000s.

Medical Applications

G13 Haze vs. Original Haze vs. G13: Comparison Table

Growing G13 Haze

G13 Haze presents moderate growing difficulty, primarily due to its sativa stretch during flowering. The 10–11 week flowering window tests grower patience but rewards it with exceptional terpene expression and a distinctive “true Haze” quality that modern fast-flower hybrids cannot replicate.

The sativa genetics mean G13 Haze will stretch significantly during the first three weeks of flowering — growers should flip to 12/12 when plants are half the intended final height. A screen of green (SCROG) setup maximizes yield by keeping the canopy even and directing energy to multiple top colas rather than one dominant central spike. The 10–11 week wait is compensated by exceptional terpene preservation and the complex, multi-layer flavor profile that shorter-flowering strains rarely achieve.

Drug Test Detection Windows

Related Strains

• Super Silver Haze — multiple Cannabis Cup winner, similar Haze family
• Original Haze — the pure sativa parent genetics
• Jack Herer — comparable award-winning Haze hybrid
• Amnesia Haze — Haze-dominant with potent cerebral effects
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