Polar Express Auto by Greenbud Seeds
A autoflowering cross of Northern Lights × Big Bud, Polar Express Auto — released by Greenbud Seeds — shows up in a lot of tents for good reason. Indoors it typically finishes flowering in around 65 days from sprout. Reported THC is 15%. The environment targets below are the same stage-by-stage bands the Cultivar journal grades real Polar Express Auto grows against.
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Similar strains
| Breeder | Greenbud Seeds |
|---|---|
| Type | ruderalis/indica/sativa |
| Flowering time | ±65 days |
| THC | 15% |
| Environment | Outdoors, Greenhouse |
| Lineage | Northern Lights × Big Bud |
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Autoflower note: runs on age, not light schedule — see the week-by-week autoflower schedule.
🧬 Explore the family: Northern Lights · Big Bud
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Growing Polar Express Auto: what to expect
Because Polar Express Auto 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 Northern Lights or Big Bud 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.
Polar Express Auto FAQ
How long does Polar Express Auto take to flower?
Polar Express Auto typically flowers in around 65 days from sprout (autoflower — no light-schedule flip needed). Individual phenotypes vary, so judge harvest readiness by trichome color, not the calendar.
Is Polar Express Auto an indica or a sativa?
Polar Express Auto is listed as ruderalis/indica/sativa (autoflowering).
What are the parents of Polar Express Auto?
Polar Express Auto was bred from Northern Lights × Big Bud by Greenbud Seeds.
How strong is Polar Express Auto?
Reported THC for Polar Express Auto is 15%. Actual potency depends heavily on environment, harvest ripeness, and cure quality.
What environment does Polar Express Auto 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 Polar Express Auto? A structured journal — with your feedings, readings, and photos — is how you find what THIS cut actually wants.
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