20 Guage by Afterthought
20 Guage is an indica-leaning cannabis strain from Afterthought, bred by crossing Ruderalis × Critical Mass. Indoors it typically finishes flowering in around 78 days after the flip to 12/12. The environment targets below are the same stage-by-stage bands the Cultivar journal grades real 20 Guage grows against.
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Similar strains
| Breeder | Afterthought |
|---|---|
| Type | ruderalis/indica/sativa |
| Flowering time | ±78 days |
| Environment | Outdoors, Greenhouse |
| Lineage | Ruderalis × Critical Mass |
| Descendants | Magnum Opus |
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🧬 Explore the family: Ruderalis · Critical Mass · Magnum Opus
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Growing 20 Guage: 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 Ruderalis or Critical Mass 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.
20 Guage FAQ
How long does 20 Guage take to flower?
20 Guage typically flowers in around 78 days after switching to a 12/12 light schedule. Individual phenotypes vary, so judge harvest readiness by trichome color, not the calendar.
Is 20 Guage an indica or a sativa?
20 Guage is listed as ruderalis/indica/sativa.
What are the parents of 20 Guage?
20 Guage was bred from Ruderalis × Critical Mass by Afterthought.
What environment does 20 Guage 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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