K-13 by Philosopher Seeds
Bred by Philosopher Seeds from Yumbolt × Western Winds, K-13 is a sativa-leaning cannabis variety. Indoors it typically finishes flowering in around 60 days after the flip to 12/12. Reported THC is 21%. The environment targets below are the same stage-by-stage bands the Cultivar journal grades real K-13 grows against.
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Similar strains
| Breeder | Philosopher Seeds |
|---|---|
| Type | mostly sativa |
| Flowering time | ±60 days |
| THC | 21% |
| Environment | Outdoors |
| Lineage | Yumbolt × Western Winds |
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Growing K-13: 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 Yumbolt or Western Winds 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.
K-13 FAQ
How long does K-13 take to flower?
K-13 typically flowers in around 60 days after switching to a 12/12 light schedule. Individual phenotypes vary, so judge harvest readiness by trichome color, not the calendar.
Is K-13 an indica or a sativa?
K-13 is listed as mostly sativa.
What are the parents of K-13?
K-13 was bred from Yumbolt × Western Winds by Philosopher Seeds.
How strong is K-13?
Reported THC for K-13 is 21%. Actual potency depends heavily on environment, harvest ripeness, and cure quality.
What environment does K-13 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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