Jack Smack is a sativa-dominant cannabis strain bred by Ustad Seeds from a Jack Herer mother and a Herijuana father, known for a pungent fuel aroma and a fast, rushing high. Leafly calls it a very powerful sativa that can overstimulate even seasoned users. AllBud lists THC at 13% to 19%, and users describe energy, focus and creativity.
Jack Smack Strain at a Glance
| Type | Sativa-dominant hybrid |
|---|---|
| Lineage | Jack Herer × Herijuana |
| Breeder / origin | Ustad Seeds |
| THC | 13–19% (typical lab range) |
| Aroma and flavor | fuel, diesel, citrus, pine, earth, lemon, lime, blueberry, woody |
| Reported effects | energetic, focused, creative, euphoric, happy |
| Best for | daytime use, productive tasks, experienced consumers |
| Flowering time | About 10 weeks |
Where Jack Smack Comes From
Jack Smack is an F1 cross from Ustad Seeds. Leafly and the breeder listing on SeedFinder both give the parents as Jack Herer and Herijuana, and the breeder specifies a long-kept Jack Herer mother and a resinous Herijuana father. Jack Herer is the famous Haze hybrid named for the cannabis activist, and Herijuana is a heavy indica known for potency.
Ustad Seeds describes the result as strong, easy to grow and mostly sativa, and notes that it has been grown in many medical gardens. It was released as regular, not feminized, seed. AllBud lists the same lineage but rates the strain as an even 50/50 hybrid, while Leafly classes it as a sativa.
Jack Smack Effects: What It Feels Like
Leafly describes a very strong sativa with a rushing euphoria and stimulation and warns users to mind the dose. Its top tags are energetic, focused and creative, and reviewers mention productivity around the house, happiness and a smooth smoke. The breeder describes a strong, fast-acting buzz that can be intense in excess, especially for less experienced smokers.
AllBud describes an energizing start that settles into physical relaxation and says the effect hits like a smack to the face. One SeedFinder grower reported two phenotypes: a larger plant with an uplifting daytime high and a shorter, tighter one with a much heavier effect. That may explain why some batches feel more balanced than others.
Jack Smack Terpenes, Aroma and Flavor
The breeder and Leafly both describe a strong, fuel-like smell. Leafly says the fuel comes from both parents and lists blueberry, earthy and woody flavors. AllBud tags citrus, diesel, earthy, pine, sour and woody aromas, and describes a spicy-sweet lemon citrus taste with pine and diesel.
Neither source lists terpene lab data, so dominant terpenes are not documented here.
Side Effects and How to Use Jack Smack
Anxiety is the top negative on Leafly, and one reviewer said it grew with repeated use. Leafly and the breeder both warn that too much can overstimulate. Keep doses small, especially if racy sativas make you uneasy.
With Jack Smack, as with any strain, a smaller dose usually avoids anxiety or grogginess. Our cannabis safety guide covers what to do if you take too much.
Do People Use Jack Smack for Medical Reasons?
Leafly users mention stress, anxiety and low mood, and its description says people use it to fight lethargy. AllBud’s listing adds fatigue and attention trouble, and one Leafly reviewer reported back pain relief. These are personal reports, not clinical findings.
These are user reports, not clinical findings. For what research actually supports, see our cannabis health and research section, and talk to your doctor before using cannabis for a health condition.
Growing Jack Smack
- Difficulty: Easy
- Flowering: About 10 weeks
- Yield: High
- Height: Tall; stretches after flip
- Environment: Indoor or outdoor
Ustad Seeds, via SeedFinder, describes an easy, high-yielding plant with large, resinous flowers when its basic needs are met. Flowering runs about 10 weeks indoors. Plants stretch a lot after the switch to 12/12, so the breeder suggests a shorter veg period, and they do best in larger pots, though sea-of-green setups also worked. A 10-week bloom finishes late outdoors, so Pacific Northwest growers should watch for autumn rain and bud rot.
Home-grow rules depend on the state: adults can grow at home in states such as California (six plants per residence), Michigan (12 per residence) and Oregon (four per household), while Washington and Illinois allow home growing only for registered medical patients. Check your state in our cannabis laws by state guide before you plant anything.
Strains Like Jack Smack
- Jack Herer: the mother, source of the energetic Haze side
- Jack Frost: another Jack Herer cross
- Super Lemon Haze: a lemony, energetic sativa
- Trainwreck: a fast-hitting, racy sativa-leaning hybrid
- Haze: the classic line behind Jack Herer
Browse more sativa strains, the full strain directory, or our guide to cannabis strains.
More Sativa Strains to Explore
Jet Fuel · Jillybean · Kali Mist · Jack of Diamonds · Jack Herer · J1 · All sativa strains
Where to Buy Jack Smack
Dispensary menus change every week, and Jack Smack may be sold under its own name, as a cross or as a pre-roll or vape. The fastest way to find it is to check store menus online before you go. In Bend, browse Bend dispensaries and check the menus at stores like Tokyo Starfish Box Factory and The Flower Room Tumalo. In San Francisco, browse San Francisco dispensaries and check the menus at stores like Harborside and Eaze San Francisco Haight. You can also browse licensed dispensaries in every state we cover. Adults 21 and older can buy with a valid photo ID; see cannabis laws by state for purchase limits.
Jack Smack FAQ
Is Jack Smack indica or sativa?
It is sativa-dominant. Leafly lists it as a sativa and the breeder calls it mostly sativa, though AllBud rates it 50/50.
What is Jack Smack a cross of?
A Jack Herer mother crossed with a Herijuana father.
Who bred Jack Smack?
Ustad Seeds.
How strong is Jack Smack?
AllBud lists 13% to 19% THC, but Leafly and the breeder both describe it as very potent and fast-hitting.
What does Jack Smack smell like?
Strong fuel and diesel with lemon, lime, pine and wood.
Where can I find Jack Smack?
It is rare at dispensaries. It has been sold as regular seed by Ustad Seeds.
For adults 21+ in legal states. Strain information reflects breeder descriptions, lab data and user reports; effects vary by person and batch. Not medical advice.
