Viper by John Sinclair Seeds
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A indica-leaning cross of Indica × Indica, Viper — released by John Sinclair Seeds — shows up in a lot of tents for good reason. Indoors it typically finishes flowering in around 58 days after the flip to 12/12. Reported THC is 22%. The environment targets below are the same stage-by-stage bands the Cultivar journal grades real Viper grows against.
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| Breeder | John Sinclair Seeds |
|---|---|
| Type | mostly indica |
| Flowering time | ±58 days |
| THC | 22% |
| Environment | Outdoors |
| Lineage | Indica × Indica |
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Growing Viper: 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 Indica 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.
Viper FAQ
How long does Viper take to flower?
Viper typically flowers in around 58 days after switching to a 12/12 light schedule. Individual phenotypes vary, so judge harvest readiness by trichome color, not the calendar.
Is Viper an indica or a sativa?
Viper is listed as mostly indica.
What are the parents of Viper?
Viper was bred from Indica × Indica by John Sinclair Seeds.
How strong is Viper?
Reported THC for Viper is 22%. Actual potency depends heavily on environment, harvest ripeness, and cure quality.
What environment does Viper 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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