Union Jack by Sagarmatha
Bred by Sagarmatha from Mostly Sativa × Indica, Union Jack is an indica-leaning cannabis variety. Indoors it typically finishes flowering in around 68 days after the flip to 12/12. The environment targets below are the same stage-by-stage bands the Cultivar journal grades real Union Jack grows against.
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Similar strains
| Breeder | Sagarmatha |
|---|---|
| Type | mostly indica |
| Flowering time | ±68 days |
| Environment | Outdoors |
| Lineage | Mostly Sativa × Indica |
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🧬 Explore the family: Mostly Sativa · Indica
Ancestry Pedigree
Original Strains
Original Strains
Growing Union 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 Mostly Sativa or Indica 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.
Union Jack FAQ
How long does Union Jack take to flower?
Union Jack typically flowers in around 68 days after switching to a 12/12 light schedule. Individual phenotypes vary, so judge harvest readiness by trichome color, not the calendar.
Is Union Jack an indica or a sativa?
Union Jack is listed as mostly indica.
What are the parents of Union Jack?
Union Jack was bred from Mostly Sativa × Indica by Sagarmatha.
What environment does Union 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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