Black Jack Autoflower by United Cannabis Seeds
Growers reach for Black Jack Autoflower as an autoflowering option, a cross of Black Jack × Ruderalis out of United Cannabis Seeds. Indoors it typically finishes flowering in around 84 days from sprout. The environment targets below are the same stage-by-stage bands the Cultivar journal grades real Black Jack Autoflower grows against.
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Similar strains
| Breeder | United Cannabis Seeds |
|---|---|
| Type | ruderalis/indica/sativa |
| Flowering time | ±84 days |
| Environment | Outdoors |
| Lineage | Black Jack × Ruderalis |
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Autoflower note: runs on age, not light schedule — see the week-by-week autoflower schedule.
🧬 Explore the family: Black Jack · Ruderalis
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The Seed Bank
Clone Only Strains
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Unknown or Legendary
Original Strains
The Seed Bank
Clone Only Strains
Unknown or Legendary
The Seed Bank
Clone Only Strains
Original Strains
Sensi Seeds
The Seed Bank
Unknown or Legendary
Original Strains
Unknown or Legendary
Sensi Seeds
The Seed Bank
Unknown or Legendary
Original Strains
Original Strains
Original Strains
Sensi Seeds
The Seed Bank
Cultivators Choice
Original Strains
Original Strains
Original Strains
Original Strains
Growing Black Jack Autoflower: what to expect
Because Black Jack Autoflower is an autoflower it runs on age, not photoperiod: keep it under 18–20 hours of light from sprout to harvest, start in its final pot, and go easy on training after week 3 — autos never pause to recover. Growers familiar with Black Jack or Ruderalis 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.
Black Jack Autoflower FAQ
How long does Black Jack Autoflower take to flower?
Black Jack Autoflower typically flowers in around 84 days from sprout (autoflower — no light-schedule flip needed). Individual phenotypes vary, so judge harvest readiness by trichome color, not the calendar.
Is Black Jack Autoflower an indica or a sativa?
Black Jack Autoflower is listed as ruderalis/indica/sativa (autoflowering).
What are the parents of Black Jack Autoflower?
Black Jack Autoflower was bred from Black Jack × Ruderalis by United Cannabis Seeds.
What environment does Black Jack Autoflower 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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Facts compiled from public breeder listings. Growing Black Jack Autoflower? A structured journal — with your feedings, readings, and photos — is how you find what THIS cut actually wants.
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