SR-71 PK by Unknown or Legendary
A indica-leaning cross of Purple Kush, SR-71 PK — released by Unknown or Legendary — shows up in a lot of tents for good reason. Indoors it typically finishes flowering in around 53 days after the flip to 12/12. The environment targets below are the same stage-by-stage bands the Cultivar journal grades real SR-71 PK grows against.
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Similar strains
| Breeder | Unknown or Legendary |
|---|---|
| Type | indica |
| Flowering time | ±53 days |
| Environment | Indoors |
| Lineage | Purple Kush |
| Descendants | Gorilla Grape Gush, Ultraviolet Haze, Epik Purple, Operation Blackbird |
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Growing SR-71 PK: 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 Purple Kush 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.
SR-71 PK FAQ
How long does SR-71 PK take to flower?
SR-71 PK typically flowers in around 53 days after switching to a 12/12 light schedule. Individual phenotypes vary, so judge harvest readiness by trichome color, not the calendar.
Is SR-71 PK an indica or a sativa?
SR-71 PK is listed as indica.
What are the parents of SR-71 PK?
SR-71 PK was bred from Purple Kush by Unknown or Legendary.
What environment does SR-71 PK 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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