Chem Sister by Clone Only Strains
If you want to talk about cannabis royalty, you have to mention Chem's Sister (or just Chem Sis). This is a straight-up elite, clone-only phenotype born from those mythical 13 seeds Chemdog scored from a bag of weed at a Grateful Dead show at Deer Creek in 1991. While her sister, the Chem '91, became the undisputed queen of the East Coast, Chem Sis carved out her own legendary status. She was officially labeled 'Chemdog A' from that first seed pop. Because she was never stabilized in seed form, keeping her alive has been a thirty-year labor of love by dedicated growers swapping cuts in the underground.
In the room, Chem Sis is known for throwing out a strong, sturdy frame with slightly more stretch than the '91. She handles topping like a champion and fills out a SCROG net beautifully. The resin production on this plant is insane, which makes sense when you remember she is the mother of Original Glue (GG4). A lot of guys on THCFarmer consider her the 'fine wine' of the Chemdog family. While Chem D drops that raunchy, garlic-and-onion body odor funk, Chem Sis is way more refined. She puts out a piercing, toasted lemon and chemical diesel aroma that literally burns your nostrils when you open a jar.
The high is where Chem Sis truly separates herself from the pack. It's a wildly euphoric, fast-acting sativa-dominant rush that feels completely electric. It doesn't drag you down into the couch; instead, it shoots you into the stratosphere with a buzzing, cerebral energy. I once saw a guy take two rips of this stuff and instantly decide to rip apart and rebuild his entire carburetor. It's just premium daytime medicine with an unmistakable sharp, fuely exhale that coats the back of your throat. Finding a verified cut of this nowadays is tough, but if you do, it's a mandatory addition to any serious genetic library.
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Similar strains
| Breeder | Clone Only Strains |
|---|---|
| Type | indica |
| Flowering time | ±70 days |
| Environment | Indoors, Outdoors |
| Lineage | Chemdog |
| Descendants | GreenMan Organic Seeds - ChemShishter, Sister City, Sisquatch, GreenMan Organic Seeds - Dragon Chem, Sis Lights, Bubba’s Sis, Grape Jelly, Tres Sister |
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🧬 Explore the family: Chemdog · GreenMan Organic Seeds - ChemShishter · Sister City · Sisquatch · GreenMan Organic Seeds - Dragon Chem · Sis Lights · Bubba’s Sis · Grape Jelly · Tres Sister
Ancestry Pedigree
Unknown or Legendary
Original Strains
Growing Chem Sister: 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 Chemdog 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.
Chem Sister FAQ
How long does Chem Sister take to flower?
Chem Sister 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 Chem Sister an indica or a sativa?
Chem Sister is listed as indica.
What are the parents of Chem Sister?
Chem Sister was bred from Chemdog by Clone Only Strains.
What environment does Chem Sister 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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