Pure Jack by 710 Genetics
Pure Jack lands on the sativa-leaning side of the spectrum, 710 Genetics's take on the Jack Herer × Unknown Strain line. Indoors it typically finishes flowering in around 74 days after the flip to 12/12. The environment targets below are the same stage-by-stage bands the Cultivar journal grades real Pure Jack grows against.
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Similar strains
| Breeder | 710 Genetics |
|---|---|
| Type | mostly sativa |
| Flowering time | ±74 days |
| Environment | Outdoors |
| Lineage | Jack Herer × Unknown Strain |
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Growing Pure Jack: what to expect
As a sativa-leaning plant, plan for a big stretch after the flip (often 100–200%) — flip earlier than feels natural and keep training options ready. Sativa-leaning plants also generally prefer a lighter feed than heavy indicas. Growers familiar with Jack Herer or Unknown Strain 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.
Pure Jack FAQ
How long does Pure Jack take to flower?
Pure Jack typically flowers in around 74 days after switching to a 12/12 light schedule. Individual phenotypes vary, so judge harvest readiness by trichome color, not the calendar.
Is Pure Jack an indica or a sativa?
Pure Jack is listed as mostly sativa.
What are the parents of Pure Jack?
Pure Jack was bred from Jack Herer × Unknown Strain by 710 Genetics.
What environment does Pure Jack 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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