Silver Jack by Seedmakers
1 other breeder's version of Silver Jack — compare flowering times side by side →
Silver Jack is a sativa-leaning cannabis strain from Seedmakers, bred by crossing Silver Haze × Jack Herer. Indoors it typically finishes flowering in around 65 days after the flip to 12/12. The environment targets below are the same stage-by-stage bands the Cultivar journal grades real Silver Jack grows against.
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Similar strains
| Breeder | Seedmakers |
|---|---|
| Type | mostly sativa |
| Flowering time | ±65 days |
| Environment | Outdoors |
| Lineage | Silver Haze × Jack Herer |
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🧬 Explore the family: Silver Haze · Jack Herer
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Growing Silver 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 Silver Haze 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.
Silver Jack FAQ
How long does Silver Jack take to flower?
Silver Jack typically flowers in around 65 days after switching to a 12/12 light schedule. Individual phenotypes vary, so judge harvest readiness by trichome color, not the calendar.
Is Silver Jack an indica or a sativa?
Silver Jack is listed as mostly sativa.
What are the parents of Silver Jack?
Silver Jack was bred from Silver Haze × Jack Herer by Seedmakers.
What environment does Silver 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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