Magnum Opus by Afterthought
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Bred by Afterthought from Big Bud × 20 Guage, Magnum Opus is an indica-leaning cannabis variety. Indoors it typically finishes flowering in around 85 days after the flip to 12/12. The environment targets below are the same stage-by-stage bands the Cultivar journal grades real Magnum Opus grows against.
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Similar strains
| Breeder | Afterthought |
|---|---|
| Type | ruderalis/indica/sativa |
| Flowering time | ±85 days |
| Environment | Outdoors, Greenhouse |
| Lineage | Big Bud × 20 Guage |
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Growing Magnum Opus: 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 Big Bud or 20 Guage 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.
Magnum Opus FAQ
How long does Magnum Opus take to flower?
Magnum Opus typically flowers in around 85 days after switching to a 12/12 light schedule. Individual phenotypes vary, so judge harvest readiness by trichome color, not the calendar.
Is Magnum Opus an indica or a sativa?
Magnum Opus is listed as ruderalis/indica/sativa.
What are the parents of Magnum Opus?
Magnum Opus was bred from Big Bud × 20 Guage by Afterthought.
What environment does Magnum Opus 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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