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FAQ

Critical Jack: frequently asked questions

Short answers to the questions people ask about Critical Jack, each with its sources.

Is Critical Jack indica or sativa?

A sativa-leaning hybrid: Dinafem, Silent Seeds and AllBud give 60% sativa, Wikileaf 55%, and Leafly and Weedmaps call it a hybrid.1,2,3,4,5,6

What strain is Critical Jack?

Dinafem Seeds’ cross of its own Critical+ with Jack Herer, bred in San Sebastián, Spain, and on sale by 2015.1,6,7

Is Critical Jack the same as Jack Herer?

No. Jack Herer, Sensi Seeds’ Dutch sativa hybrid, is one of Critical Jack’s two parents; Critical+ is the other.7,8

Is Critical Jack Herer the same strain?

Not necessarily. Leafly lists Critical Jack Herer as another name for Critical Jack, but Delicious Seeds of Valencia sells a different cross, Critical Mass × Jack Herer, under that name.5,9

How much THC is in Critical Jack?

The median is 15.01% across only eight tests, a small sample; the eight results ran from 7.55% to 21.55%.10 Dinafem lists 15–20% and Leafly 20%.1,5

Does Critical Jack have CBD?

Very little: 2 of the 4 tests that reported CBD found none, none reached 1%, and the highest was 0.20%.10 Dinafem lists 0.01–0.2%.1

What terpenes are in Critical Jack?

Our lab data cannot say: only one of the eight tests reported individual terpene values, too few for a profile.10 Leafly lists terpinolene as dominant, followed by caryophyllene and pinene.5

What does Critical Jack taste and smell like?

Lemon, pine and incense: Leafly users list pine, citrus and lemon; Dinafem describes wood, incense, pine, spices and lemon; AllBud adds a spicy pepper aroma.1,3,5

Does Critical Jack make you sleepy?

Not according to user reports: Leafly’s top effects are focused, energetic and uplifted, and AllBud calls it a daytime strain. Weedmaps adds a warm, relaxing body side.3,5,6

Who bred Critical Jack?

Dinafem Seeds, a Basque seed bank founded in 2005 in San Sebastián; Weedmaps says it pollinated its Critical+ with a Jack Herer male from Sensi Seeds.6,11,12

Can you still buy Dinafem’s Critical Jack seeds?

Not from Dinafem: its pages say "We currently do not sell seeds on this website", and in November 2023 the company said the judicial authority forbade it to resume sales. Silent Seeds, which calls itself Dinafem’s sole heir, lists a Critical Jack it says comes from the same clones. This site does not sell seeds.1,13,14,15

What is Critical Jack Auto?

Dinafem’s Critical Jack Autoflowering is a different cross, Critical+ 2.0 × Haze 2.0 Autoflowering, 60% indica with 10–15% THC and a 70–80 day cycle; Delicious Seeds’ Critical Jack Herer Auto is Critical Mass Auto × Jack Herer Auto.16,17

How long does Critical Jack take to flower?

About 60 days indoors: Dinafem and Silent Seeds say 60, Weedmaps 63, SeedFinder 55–65 and Wikileaf 57–67; outdoors it finishes from late September to mid-October.1,2,4,6,18

Where can I buy Critical Jack?

Only from licensed stores where cannabis is legal for you, and it is rare. On Oct 3, 2026, Weedmaps showed Critical Jack flower at 2 store listings in 1 of 27 US markets, all within 50 miles of Detroit; the other 26 markets, including Los Angeles, Denver and New York, had none.19

Sources

  1. Dinafem Seeds, Critical Jack: feminized seeds, specifications, lab analysis and awards. Accessed Oct 3, 2026.
  2. Silent Seeds, Critical Jack feminized seeds. Accessed Oct 3, 2026.
  3. AllBud, Critical Jack marijuana strain information and reviews. Accessed Oct 3, 2026.
  4. Wikileaf, Critical Jack strain. Accessed Oct 3, 2026.
  5. Leafly, Critical Jack aka Critical Jack Herer strain information. Accessed Oct 3, 2026.
  6. Weedmaps, Critical Jack strain page. Accessed Oct 3, 2026.
  7. Dinafem Seeds, Critical Jack feminised marijuana strain (Dinafem TV). Accessed Oct 3, 2026.
  8. Leafly, Jack Herer strain information. Accessed Oct 3, 2026.
  9. Delicious Seeds, Critical Jack Herer feminized seeds. Accessed Oct 3, 2026.
  10. Cannlytics (CC BY 4.0), cannabis_results: public state lab results (filtered and aggregated by Official Cannabis). Accessed Oct 3, 2026.
  11. High Times, An interview with Dinafem Seeds: Europe’s king of feminized seeds (Stoney Tark) (2019-03-14). Accessed Oct 3, 2026.
  12. Dinafem Seeds, Dinafem Seeds (home page: company address and seed-sales notice). Accessed Oct 3, 2026.
  13. Newsweed, Dinafem donne de ses nouvelles, une première depuis 2020 (2023-11-27). Accessed Oct 3, 2026.
  14. Silent Seeds, Silent Seeds, the sole heir to Dinafem Seeds (home page). Accessed Oct 3, 2026.
  15. SeedFinder, Critical Jack (Silent Seeds): strain info. Accessed Oct 3, 2026.
  16. Dinafem Seeds, Critical Jack Autoflowering. Accessed Oct 3, 2026.
  17. Delicious Seeds, Critical Jack Herer Auto. Accessed Oct 3, 2026.
  18. SeedFinder, Critical Jack (Dinafem): strain info, breeder description and grow reports. Accessed Oct 3, 2026.
  19. Weedmaps listings, compiled by Official Cannabis, Weedmaps flower menu snapshot, 27 US markets, Oct 3, 2026. Accessed Oct 3, 2026.