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Black Jack Feminized
Potent feminized sativa with euphoric and focused effects and vigorous vegetative growth. Ideal for intermediate growers seeking stable genetics and strong production.
◉Flavor:Sweet fruit, peppery spice, fresh pine
Grower tip: Flip to 12/12 early, sativas stretch 2–3× in flower
Premium stabilized genetics · germination guaranteed
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About Black Jack Feminized
We have run Black Jack across multiple environments now, and what stands out is the consistency. Whether in a 3x3 tent under LED or a 4x4 with HPS, this sativa delivers a pinene-forward flower at 23% THC that matches the genetic promise. The 20/80 profile shows in how the plant structures itself, vertical, energetic, always reaching for the light. From germination through cure, this is a straightforward cultivar that rewards basic competence without demanding perfection.
What Growers Typically Observe With This Strain
The vegetative phase is unremarkable in the best possible way, steady, consistent growth with no drama in published cultivation reports. After topping at node 4, plants commonly bush out aggressively and fill a 3x3 space by week 5 of veg. The stretch after flipping is significant, close to 50% height gain in the first 10 days after flip.
Flowering completes in 9-11 weeks. Trichome development typically accelerates in weeks 5-6, and the pinene aroma becomes unmistakable by week 7. Typical indoor yield: 450-550g/m² under LED. Height at harvest: Compact (2-3 ft). Difficulty: intermediate, nothing here that would intimidate a grower with one successful harvest behind them.
The one thing to watch: calcium demand commonly spikes under intense LED light, faster growth under high PPFD can outpace a standard cal-mag dosing schedule.
Effects and Use
At 23% THC, Black Jack delivers euphoric, focused, energetic effects with a pinene-influenced character. The onset is cerebral, a brightening of the mental space that arrives within minutes and can enhance focus, creativity, and conversation for 2-3 hours before gradually softening. The body stays comfortable without heaviness. The pinene dominance adds a clarity that many users describe as "functional".
Terpene Profile
Dominant terpenes: Pinene (primary), Limonene (secondary), Caryophyllene (tertiary). This combination produces an aroma profile that is immediately identifiable when the jar opens and translates well to both vaporization (best at 360-385°F) and combustion, though lower temperatures preserve the limonene top notes that combustion destroys.
Who Should Grow Black Jack
Best suited for growers who want control over their plant size and harvest timing, photoperiod genetics let you veg as long as you want before triggering flower. The intermediate difficulty rating means basic growing competence is sufficient, but attention to detail during flower produces noticeably better results. Ships discreetly to all 50 US states with our germination guarantee.
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Black Jack Strain Review
Want the full breakdown of effects, lineage, terpene profile, and a complete grow guide? Read our in-depth Black Jack strain review.
Black Jack Feminized, Cannabinoid & Terpene Reference
Reference ranges aggregated from publicly-reported third-party lab data and breeder documentation. Total THC reported as max-potential (THC + 0.877 × THCA). Individual seed-lot expression may vary by 1-3 percent.
Black Jack Feminized, Aggregated Grower Yield Reports
Yield ranges aggregated from public grower journals, breeder-documented spec sheets, and cultivation community reports on Black Jack Feminized feminized seeds. First-time growers should expect 70-85 percent of these numbers.
| Setup | Yield |
|---|---|
| 5×5 tent, 1000W HPS, ScrOG + topping | 475g |
| Outdoor, raised bed, full sun | 770g |
Black Jack Feminized, Sourcing & Genetics
Black Jack Feminized was bred in Spain by a respected European seed bank and selected for stability across multiple climates before reaching the US market.
Best in long-season warm climates (CA, OR, FL, HI, Southern states). Indoor cultivation works in any climate.
Black Jack Feminized, Breeder Information
Royal King GeneticsBred and stabilized in-house by Royal King Genetics , our internal breeding team. Every order is backed by our 95% germination guarantee. Read our full breeding process and about page.
Black Jack runs through our F3 program. Most of the pack expresses the target haze-character terps cleanly; the F3-to-F4 cycle is where we close out the last off-types.
Stabilize Black Jack across three generations toward F4 production-ready stock.
Selected for sativa vigor, bud-to-leaf ratio, and the distinctive terpene expression of the original cut.
Royal King Genetics breeding program, pollen from selected sibling males of the recurrent parent.