Grandaddy Pupil by MassMedicalStrains
Growers reach for Grandaddy Pupil as an indica-leaning option, a cross of Star Pupil × Grand Daddy Purple out of MassMedicalStrains. Indoors it typically finishes flowering in around 70 days after the flip to 12/12. The environment targets below are the same stage-by-stage bands the Cultivar journal grades real Grandaddy Pupil grows against.
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Similar strains
| Breeder | MassMedicalStrains |
|---|---|
| Type | mostly indica |
| Flowering time | ±70 days |
| Environment | Outdoors, Greenhouse |
| Lineage | Star Pupil × Grand Daddy Purple |
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🧬 Explore the family: Star Pupil · Grand Daddy Purple
Ancestry Pedigree
MassMedicalStrains
Unknown or Legendary
Original Strains
Unknown or Legendary
Unknown or Legendary
Cultivators Choice
Original Strains
Original Strains
Original Strains
Unknown or Legendary
Original Strains
Growing Grandaddy Pupil: 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 Star Pupil or Grand Daddy Purple 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.
Grandaddy Pupil FAQ
How long does Grandaddy Pupil take to flower?
Grandaddy Pupil typically flowers in around 70 days after switching to a 12/12 light schedule. Individual phenotypes vary, so judge harvest readiness by trichome color, not the calendar.
Is Grandaddy Pupil an indica or a sativa?
Grandaddy Pupil is listed as mostly indica.
What are the parents of Grandaddy Pupil?
Grandaddy Pupil was bred from Star Pupil × Grand Daddy Purple by MassMedicalStrains.
What environment does Grandaddy Pupil 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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