Sir Jack by Exotic Seed
1 other breeder's version of Sir Jack — compare flowering times side by side →
Growers reach for Sir Jack as a sativa-leaning option, a cross of Jack Herer out of Exotic Seed. Indoors it typically finishes flowering in around 63 days after the flip to 12/12. The environment targets below are the same stage-by-stage bands the Cultivar journal grades real Sir Jack grows against.
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Similar strains
| Breeder | Exotic Seed |
|---|---|
| Type | mostly sativa |
| Flowering time | ±63 days |
| Environment | Outdoors |
| Lineage | Jack Herer |
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Growing Sir 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 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.
Sir Jack FAQ
How long does Sir Jack take to flower?
Sir Jack typically flowers in around 63 days after switching to a 12/12 light schedule. Individual phenotypes vary, so judge harvest readiness by trichome color, not the calendar.
Is Sir Jack an indica or a sativa?
Sir Jack is listed as mostly sativa.
What are the parents of Sir Jack?
Sir Jack was bred from Jack Herer by Exotic Seed.
What environment does Sir 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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