Ultra Chem SFV by Unknown or Legendary

Cross Chemdog × SFV OG

There are certain cuts floating around the underground that never see a commercial seed drop, and Ultra Chem SFV is one of those legendary phantoms. This is a heavy-duty hybrid believed to be a clash of the titans: raw Chemdawg genetics crossed with the infamous San Fernando Valley (SFV) OG Kush. The "Ultra" tag usually means you're dealing with a highly specific, closely guarded clone-only selection or a localized repro project that guys have been passing around in unlabelled envelopes for years. It's got that classic, aggressive terpene profile loaded with myrcene and limonene that just assaults your nostrils with lemon, pine, and straight jet fuel.

Growing this plant separates the men from the boys. Like most elite OG and Chem lines, she can be a finicky feeder and highly sensitive to light intensity. If you blast her with too much light, you'll see bleaching, but if you dial in the canopy and keep the feed on point, she pumps out some of the greasiest, most resin-caked nugs you've ever laid eyes on. Old heads over at ICMag and Overgrow have filled pages of journals trying to stabilize or reproduce these exact traits, noting that while the yield might not break records, the quality of the smoke is absolute top-tier headstash.

Because this cut was never standardized or boxed up by a big seed company, there's always a bit of mystery surrounding exactly which Chem or which SFV mother was used. That just adds to the mythos. When you finally get your hands on a legit Ultra Chem SFV cut and take that first pull, it's a lung-expanding, spicy, gassy blast that hits your brain like a freight train before melting down into your body. It's a true connoisseur's plant, held tight by the growers who know what real power tastes like.

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Similar strains

Longbottom LeafUnknown or LegendaryChem DazeUnknown or LegendaryOriginal DieselUnknown or LegendaryChemdog HazeUnknown or LegendaryChemdog #4 x Alien OGUnknown or LegendaryBotch ToeUnknown or Legendary · ±80 daysAll Unknown or Legendary →
BreederUnknown or Legendary
EnvironmentIndoors, Outdoors
LineageChemdog × SFV OG
DescendantsThunderfudge - Golden Retriever, Ultra La Chem, Ultrabrite, Super Lemon Dawgfighter, Sweet and Sour Chem, Ultimate Chem 818, Dead Dawgs Walk'n SFV, OGK Knuckle Draggerz, Ultimate Lemon Bubba

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🧬 Explore the family: Chemdog · SFV OG · Thunderfudge - Golden Retriever · Ultra La Chem · Ultrabrite · Super Lemon Dawgfighter · Sweet and Sour Chem · Ultimate Chem 818 · Dead Dawgs Walk'n SFV · OGK Knuckle Draggerz

Ancestry Pedigree

Chemdog
Unknown or Legendary
Indica Sativa
Original Strains
SFV OG
Clone Only Strains
OG Kush
Clone Only Strains
Unknown Strain
Original Strains
Hindu Kush Indica
Original Strains

Growing Ultra Chem SFV: what to expect

As a hybrid, expect a moderate stretch after the flip (around 100%) — but watch the plant, not the label: phenotypes within Ultra Chem SFV can lean either direction. Growers familiar with Chemdog or SFV OG 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.

Ultra Chem SFV FAQ

Is Ultra Chem SFV an indica or a sativa?

The breeder doesn't specify — treat it as a hybrid and read the plant.

What are the parents of Ultra Chem SFV?

Ultra Chem SFV was bred from Chemdog × SFV OG by Unknown or Legendary.

What environment does Ultra Chem SFV 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 Ultra Chem SFV? A structured journal — with your feedings, readings, and photos — is how you find what THIS cut actually wants.

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Published by Cultivar (logmygrow.com), a structured grow journal. These reference bands are the same ones the app grades real grows against. Free to cite with a link. Some outbound product links are affiliate links — see disclosures.