Mk-Ultra by TH Seeds
When T.H. Seeds dropped MK-Ultra on the Amsterdam scene in the early 2000s, it completely shifted the paradigm of what a heavy indica could be. Named after the CIA's infamous 1950s mind-control experiments, this strain wasn’t just given a catchy moniker—it actually earned it by putting seasoned smokers into a trance. The genetic makeup is the stuff of legend, crossing the mythical, ultra-potent G-13 with a prime cut of OG Kush straight out of Los Angeles. The result was a devastatingly strong hybrid that stormed the High Times Cannabis Cup, taking home 1st place Indica in 2003 and backing it up with a 2nd place finish in 2004.
In the garden, MK-Ultra is a dream to run. It leans heavily on its G-13 heritage, maintaining a manageable, squat profile that usually finishes around 90 to 130 cm tall. It doesn’t stretch much when you flip the lights, instead focusing all its energy on stacking incredibly dense, resin-drenched rocks over a standard 8 to 9 week flowering cycle. Growers on the forums always praised its stability and favorable calyx-to-leaf ratio, making harvest time a breeze. The trichome production is so aggressive that the fan leaves often curl under the weight of the resin, making it a stellar choice for hash makers looking for that premium, full-melt return.
The terpene profile is old-school gas and earth at its finest. You get hit in the face with a sharp, pine-forward chemical blast, rounded out by deep, musty earth and a hint of that classic OG citrus bite. But the real reason growers keep MK-Ultra cuts alive for decades is the effect. The high hits fast and cerebral, instantly living up to its "hypnotic" reputation by wrapping your brain in a heavy fog, before rapidly melting down the neck into a bone-deep, narcotic body stone. It is a true day-ruiner in the best way possible, offering unmatched relief for pain and insomnia.
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Similar strains
| Breeder | TH Seeds |
|---|---|
| Type | mostly indica |
| Flowering time | ±58 days |
| Environment | Outdoors, Greenhouse |
| Lineage | G-13 × OG Kush |
| Descendants | Auto MK-Ultra Kush, Flex Fuel, Sour Kush, MKage, UltraSour, Unholywood, MK-Ultra Kush x Bubblegum, MK-Ultra Cake, Kultranusta, U-God, Big Tuna, Ultra Alien, Tangerine Kush, TH Seeds - MK-Ultrawreck, Seedsman - Power Africa x MK Ultra FAST, MK Ultra x Creamsicle, CBD Ultra, Cold Creek Kush, Tangerine Kush, MK Ultra Black Ops, MK LAV |
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🧬 Explore the family: G-13 · OG Kush · Auto MK-Ultra Kush · Flex Fuel · Sour Kush · MKage · UltraSour · Unholywood · MK-Ultra Kush x Bubblegum · MK-Ultra Cake
Ancestry Pedigree
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Original Strains
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Growing Mk-Ultra: 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 G-13 or OG Kush 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.
Mk-Ultra FAQ
How long does Mk-Ultra take to flower?
Mk-Ultra typically flowers in around 58 days after switching to a 12/12 light schedule. Individual phenotypes vary, so judge harvest readiness by trichome color, not the calendar.
Is Mk-Ultra an indica or a sativa?
Mk-Ultra is listed as mostly indica.
What are the parents of Mk-Ultra?
Mk-Ultra was bred from G-13 × OG Kush by TH Seeds.
What environment does Mk-Ultra 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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