Birrie Jack by Amaranta Seeds
Birrie Jack is an indica-leaning cannabis strain from Amaranta Seeds, bred by crossing Critical Jack × Roadrunner Automatic. 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 Birrie Jack grows against.
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| Breeder | Amaranta Seeds |
|---|---|
| Type | ruderalis/indica/sativa |
| Flowering time | ±60 days |
| Environment | Outdoors |
| Lineage | Critical Jack × Roadrunner Automatic |
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Growing Birrie 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 Jack or Roadrunner Automatic 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.
Birrie Jack FAQ
How long does Birrie Jack take to flower?
Birrie 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 Birrie Jack an indica or a sativa?
Birrie Jack is listed as ruderalis/indica/sativa.
What are the parents of Birrie Jack?
Birrie Jack was bred from Critical Jack × Roadrunner Automatic by Amaranta Seeds.
What environment does Birrie 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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