Critical Jack by Dinafem
2 other breeders' versions of Critical Jack — compare flowering times side by side →
Critical Jack, from breeder Dinafem, is an indica-leaning strain descended from Critical Plus × Jack Herer. Indoors it typically finishes flowering in around 60 days after the flip to 12/12. The environment targets below are the same stage-by-stage bands the Cultivar journal grades real Critical Jack grows against.
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Similar strains
| Breeder | Dinafem |
|---|---|
| Type | indica/sativa |
| Flowering time | ±60 days |
| Environment | Outdoors |
| Lineage | Critical Plus × Jack Herer |
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🧬 Explore the family: Critical Plus · Jack Herer
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Growing Critical Jack: 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 Critical Plus or Jack Herer 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.
Critical Jack FAQ
How long does Critical Jack take to flower?
Critical Jack typically flowers in around 60 days after switching to a 12/12 light schedule. Individual phenotypes vary, so judge harvest readiness by trichome color, not the calendar.
Is Critical Jack an indica or a sativa?
Critical Jack is listed as indica/sativa.
What are the parents of Critical Jack?
Critical Jack was bred from Critical Plus × Jack Herer by Dinafem.
What environment does Critical 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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