Sativa-Dominant Hybrid

Jack Herer

The award-winning sativa legend bred by Sensi Seeds in 1994. Named after cannabis activist Jack Herer — 7+ Cannabis Cup wins, terpinolene-dominant, 18–23% THC.

18–23% THC Sativa 55/45 7–10 wks flower Terpinolene Sensi Seeds 1994
20%
Avg THC
Range 18–23%
0.1%
CBD
Trace levels
55/45
Sativa/Indica
Near-balanced
7–10w
Flower Time
50–70 days
7+
Cannabis Cups
Since 1994

Key Findings

Genetics & Origin

Jack Herer was created by Ben Dronkers at Sensi Seeds in Amsterdam around 1994, with the explicit goal of combining the resin production of NL#5, the vigour of Shiva Skunk, and the cerebral effect profile of classic Haze. The result was a near-hybrid with sativa-dominant phenotype expression.

The strain was named after Jack Herer, the American cannabis activist who wrote The Emperor Wears No Clothes in 1985 — a book arguing that hemp prohibition was driven by petrochemical and timber industry lobbying rather than public health concerns. Herer corresponded with Sensi Seeds and gave his blessing to the naming.

Lineage Tree

ParentTypeKey Trait Contributed
Northern Lights #5IndicaResin production, compact structure, resilience
Shiva SkunkNL#5 × Skunk #1Vigour, yield, pungent aroma base
HazePure SativaCerebral effect, terpinolene terpene profile, long flower

Because Sensi Seeds never disclosed the exact backcross ratios, several phenotypes exist in the market — some lean more indica with a shorter flower time, others express more strongly sativa with a longer stretch. The original "A" phenotype is the most prized for competition use.

Terpene Profile & Effects

Jack Herer is one of a small group of strains where terpinolene is the dominant terpene — a characteristic shared with Durban Poison, Ghost Train Haze, and Dutch Treat. Research (Russo, 2011; Steep Hill Labs data 2017) associates terpinolene-dominant profiles with uplifting, socially engaging effects and reduced sedation.

TerpeneAvg %Aroma NotesEffect Association
Terpinolene0.52%Piney, floral, herbalUplifting, energising
Ocimene0.28%Sweet, herbal, citrusAnti-inflammatory (preclinical)
Caryophyllene0.19%Spicy, pepper, woodyCB2 agonist, stress modulation
Myrcene0.14%Earthy, musky, mangoMild sedation at high levels
Pinene0.09%Sharp pineMemory retention (preclinical)

Terpinolene-Dominant Strains: Comparison

StrainTHCTypeTerpinolene %Flower Time
Jack Herer18–23%Sativa 55/45~0.52%7–10 wks
Durban Poison15–20%Pure Sativa~0.45%8–9 wks
Ghost Train Haze20–27%Sativa-dom~0.60%10–11 wks
Dutch Treat18–22%Hybrid~0.38%7–8 wks

Users commonly report jack herer as producing a clear-headed, creative, and conversation-friendly high. It is rarely associated with couch-lock at standard doses. The balanced hybrid genetics mean the body remains comfortable while the mind stays alert — a profile that explains its historical popularity as a daytime medical strain in the Netherlands.

Grow Guide

Jack Herer is classified as intermediate difficulty. The main challenge is managing vertical stretch during the first 3 weeks of flower — plants can double in height. Indoor growers should flip to 12/12 when plants reach 40–50% of the desired final height.

ParameterIndoorOutdoor
Flower time50–70 daysMid-October harvest
Yield400–550 g/m²500–700 g/plant
Plant height90–150 cm (trained)180–250 cm
Temp range20–26°C dayTemperate climate
Humidity (flower)40–50% RHLow humidity preferred
TrainingLST or topping at node 4Minimal needed
DifficultyIntermediate — stretch management key

Jack Herer is resistant to powdery mildew and performs well in hydroponic setups. The resinous buds are dense enough to be susceptible to bud rot in high humidity — keep airflow strong and relative humidity below 50% during flower. Flushing 10–14 days before harvest improves the terpene expression in the final product.

Medical & Award History

Jack Herer holds a unique dual status in cannabis: it is both a high-profile recreational strain and a government-approved medical product. The Dutch Office for Medicinal Cannabis (OMC) licensed a Jack Herer-derived cultivar for pharmacy dispensing under the Bedrocan brand — a rare distinction confirming its quality at pharmaceutical standards.

YearRecognitionCategory
1994Bred by Sensi Seeds, AmsterdamOrigin
1994–20007× High Times Cannabis Cup winsBest Sativa / Best Overall
2001Dutch Office for Medicinal Cannabis approvalMedical (Bedrocan)
2004Emerald Cup — Heritage strain recognitionLegacy
2010Jack Herer (activist) passes; strain renamed at many events in tributeTribute
OngoingWorldwide seed bank availability — 500+ licensed phenotypesGenetics

Cannabis Cup judging data (reported in High Times 1994–2000) consistently rated Jack Herer highest on aroma and effect profile among sativa-dominant entries. Its 7 consecutive wins in the 1990s — before most modern strains existed — cement it as a historically significant cultivar.

Frequently Asked Questions

Who is Jack Herer the strain named after?
The strain is named after Jack Herer (1939–2010), American cannabis activist and author of 'The Emperor Wears No Clothes' (1985), one of the most influential books in cannabis legalisation history. Sensi Seeds bred the strain in the Netherlands in 1994 as a tribute to his advocacy work.
What are Jack Herer's main terpenes?
Jack Herer is dominated by terpinolene (piney, floral, herbaceous), followed by ocimene (sweet, herbal) and caryophyllene (spicy, peppery). This terpene profile is characteristic of classic Dutch sativa genetics and produces an uplifting, cerebral effect with minimal sedation.
How long does Jack Herer take to flower?
Jack Herer flowers in 50–70 days (7–10 weeks) indoors. Outdoor harvest typically falls in mid-October in the Northern Hemisphere. It is a moderately tall plant that can stretch considerably during early flower — topping or LST training is recommended for indoor grows.
Is Jack Herer suitable for anxiety or depression?
Jack Herer is one of the most commonly cited strains for daytime mood support. Its high terpinolene and moderate THC content (18–23%) tend to produce an energetic, euphoric effect without heavy sedation. However, high doses may increase anxiety in THC-sensitive individuals — start low, especially if prone to paranoia.
JP

Jordan Price

Jordan Price covers cannabis genetics, terpene science, and cultivation at ZenWeedGuide. With a background in plant biology and 8+ years researching cannabis cultivars, Jordan focuses on evidence-based strain analysis grounded in published terpene data and documented grow performance.