# Critical Jack

> Critical Jack is a sativa-leaning hybrid of Critical+ and Jack Herer bred by Dinafem Seeds of San Sebastián, in Spain’s Basque Country. It tests at a median total THC of 15.01% across 8 state lab tests of Critical Jack flower, with the middle half of results between 13.41% and 20.68%: only eight tests, far too few to show a typical range. Leafly lists focused, energetic and uplifted as its top effects, from user reports.

Published by Official Cannabis (https://officialcannabis.net). Lab statistics: 8 state lab tests (small sample), median total THC 15.01%, middle half 13.41%–20.68% (Cannlytics cannabis_results, CC BY 4.0, analysis by Official Cannabis).

## Guide
- [Strain overview](https://criticaljack.com/): Critical Jack is Dinafem’s Critical+ × Jack Herer hybrid from Spain. Median THC in only eight US lab tests: 15.01%, a small sample. Genetics, grow, effects.
- [Genetics](https://criticaljack.com/genetics/): Critical Jack is Dinafem’s Critical+ (Big Bud × Skunk) × Sensi Seeds’ Jack Herer. Where Critical+ comes from, how sativa it is, and the other Critical Jacks.
- [THC and terpenes](https://criticaljack.com/potency/): Critical Jack tested at 15.01% median THC in only eight US lab tests from Massachusetts and Michigan: a very small sample. Breeder figures, CBD and caveats.
- [Effects](https://criticaljack.com/effects/): Leafly’s top effects for Critical Jack are focused, energetic and uplifted; breeders call it cerebral and long-lasting. Downsides: anxious, dry mouth, dry eyes.
- [Growing](https://criticaljack.com/grow/): Critical Jack flowers in about 60 days indoors and finishes outdoors from late September; Dinafem claims 625 g/m² and 3 m plants. Breeder specs side by side.
- [Where to find it](https://criticaljack.com/near-me/): Critical Jack flower is scarce in US stores: 2 Weedmaps listings in 1 of 27 markets on Oct 3, 2026. Store counts by market and the European seed trade.
- [History](https://criticaljack.com/history/): How a Basque seed bank crossed Critical+ with Jack Herer, won cups, was shut down by a 2020 police operation and saw its genetics move to Rotterdam.
- [FAQ](https://criticaljack.com/faq/): Answers to the top questions about Critical Jack: indica or sativa, parents, THC, CBD, taste, sleepiness, breeder, autos, flowering time and where to buy.

## Comparisons
- [Critical Jack vs Jack Herer](https://criticaljack.com/vs/jack-herer/): Critical Jack vs Jack Herer: Dinafem’s cross against its Sensi Seeds parent, compared on state-lab THC, lineage, effects, flavor and flowering time.
- [Critical Jack vs Super Lemon Haze](https://criticaljack.com/vs/super-lemon-haze/): Critical Jack vs Super Lemon Haze: two European-bred lemon sativa hybrids compared on state-lab THC, lineage, effects, flavor and flowering time.
- [Critical Jack vs Blue Dream](https://criticaljack.com/vs/blue-dream/): Critical Jack vs Blue Dream: a Spanish seed-bank cross against America’s best-selling strain, compared on state-lab THC, lineage, effects and store counts.
- [Critical Jack vs Sour Diesel](https://criticaljack.com/vs/sour-diesel/): Critical Jack vs Sour Diesel: lemon and pine against fuel, compared on state-lab THC, lineage, effects, flavor and how often US stores carry them.
- [Critical Jack vs Durban Poison](https://criticaljack.com/vs/durban-poison/): Critical Jack vs Durban Poison: a Spanish hybrid against a South African landrace sativa with the same reported effects, compared on lab THC and lineage.
- [Critical Jack vs G13 Haze](https://criticaljack.com/vs/g13-haze/): Critical Jack vs G13 Haze: Dinafem’s Spanish cross against Barney’s Farm’s Amsterdam Haze hybrid, two small lab samples compared on THC, lineage and effects.

## Data
- [Lab test CSV](https://criticaljack.com/data/critical-jack-lab-tests.csv): one row per test (state, date, lab, product, THC, CBD, terpenes)
- [Full text for LLMs](https://criticaljack.com/llms-full.txt)