Jack Horrendus by Jah Seeds
A indica-leaning cross of Flavius Horrendus × Jack Herer, Jack Horrendus — released by Jah Seeds — shows up in a lot of tents for good reason. Indoors it typically finishes flowering in around 64 days after the flip to 12/12. The environment targets below are the same stage-by-stage bands the Cultivar journal grades real Jack Horrendus grows against.
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Similar strains
| Breeder | Jah Seeds |
|---|---|
| Type | 65% indica/35% Sativa |
| Flowering time | ±64 days |
| Environment | Outdoors |
| Lineage | Flavius Horrendus × Jack Herer |
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Growing Jack Horrendus: 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 Flavius Horrendus 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.
Jack Horrendus FAQ
How long does Jack Horrendus take to flower?
Jack Horrendus typically flowers in around 64 days after switching to a 12/12 light schedule. Individual phenotypes vary, so judge harvest readiness by trichome color, not the calendar.
Is Jack Horrendus an indica or a sativa?
Jack Horrendus is listed as 65% indica/35% Sativa.
What are the parents of Jack Horrendus?
Jack Horrendus was bred from Flavius Horrendus × Jack Herer by Jah Seeds.
What environment does Jack Horrendus 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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