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Sour Jack Feminized
Mellow feminized sativa with uplifted and energetic effects and extended stretch and airy colas. Ideal for intermediate growers seeking potency and reliable yields.
◉Flavor:Orange zest, pine, sandalwood
Grower tip: Use a scrog net at week 3 to manage stretch and maximize light
Premium stabilized genetics · germination guaranteed
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About Sour Jack Feminized
The most common mistake growers make with Sour Jack is not flipping early enough. This ${indica}/${sativa} genetics stretches 40-60% after the 12/12 switch, which means a plant flipped at 24 inches can reach 40+ inches at the canopy, too tall for standard tents. Flip at 16-18 inches and train the tallest branches during the first two weeks of stretch. At 15% THC with limonene-dominant terpenes, the quality ceiling is high, but you have to manage the specific characteristics of this cultivar to reach it.
Growing This Strain: Where Things Go Right and Wrong
The three most common issues growers report with Sour Jack:
1. Nutrient timing at the flip. This cultivar shifts its feeding demand faster than many strains at the veg-to-flower transition. Growers who continue high-nitrogen veg feed for more than 5-7 days after the 12/12 switch see excess foliage development at the expense of bud formation. Switch to bloom nutrients within the first week of seeing pistils.
**2. Height management. The stretch surprises indoor growers who flip too late. In a 5-foot tent, flip when the plant is 16-18 inches. Under LED the stretch is slightly less than HPS, but still significant. Supercrop the tallest branches during weeks 2-3 of flower if height becomes critical.
3. Harvest timing. With limonene as the dominant terpene, the aromatic peak does not align perfectly with the trichome maturity peak. Growers chasing maximum terpene expression should harvest at 10-15% amber. Growers prioritizing potency should wait for 15-20% amber. These are different windows, know which one you are targeting.
Flowering: 9-11 weeks. Yield: 400-500g/m² indoor / 350-500g/plant outdoor. Height: Compact (2-3 ft). Difficulty: intermediate.
Effects and Use
At 15% THC, Sour Jack delivers uplifted, energetic effects with a limonene-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 limonene dominance keeps the mental space bright and slightly elevated even when the body relaxes.
Terpene Profile
Dominant terpenes: Limonene (primary), Pinene (secondary), Terpinolene (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 pinene top notes that combustion destroys.
Who Should Grow Sour 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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Sour 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.
Sour Jack Feminized, Aggregated Grower Yield Reports
Yield ranges aggregated from public grower journals, breeder-documented spec sheets, and cultivation community reports on Sour Jack Feminized feminized seeds. First-time growers should expect 70-85 percent of these numbers.
| Setup | Yield |
|---|---|
| 5×5 tent, 1000W HPS, ScrOG + topping | 482g |
| 4×4 tent, 1000W HPS, SCROG | 482g |
Sour Jack Feminized, Sourcing & Genetics
Sour Jack Feminized traces its lineage back to landrace genetics from Asia and was modernized through North American breeders selecting for terpene complexity.
Best in long-season warm climates (CA, OR, FL, HI, Southern states). Indoor cultivation works in any climate.
Sour 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.
A West Coast clone-only clone-only original brought to seed via a three-generation backcross program. Vigor, terpene character, and finished-flower potency are locked. The seed pack runs true to the cut your friend grew off a clone last year.
Lock the finished-flower potency of the elite cut into the population.
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.