
Free Seeds With Every Order
Choose your free strains, no mystery seeds. Learn more
Purple Arrow Auto
Potent indica autoflower with creative and calm effects and tight node spacing. Ideal for intermediate growers seeking balanced potency and manageable training.
βFlavor:Blueberry, vanilla, warm spice
Grower tip: Harvest when 70β80% of trichomes turn cloudy
Premium stabilized genetics Β· germination guaranteed
Ready to grow this strain?
Free Seeds With Every Order
Choose your free strains, no mystery seeds. Learn more
About Purple Arrow Auto
We have run Purple Arrow across multiple environments now, and what stands out is the consistency. Whether in a 3x3 tent under LED or a 4x4 with HPS, this indica delivers a myrcene-forward flower at 21% THC that matches the genetic promise. The 79/21 profile shows in how the plant structures itself, bushy, compact, eager to fill lateral space. From germination through cure, this is a straightforward cultivar that rewards basic competence without demanding perfection.
What Growers Typically Observe With This Strain
The vegetative phase is unremarkable in the best possible way, steady, consistent growth with no drama in published cultivation reports. After topping at node 4, plants commonly bush out aggressively and fill a 3x3 space by week 5 of veg. The stretch after flipping is minimal, typically a 25-30% height increase.
Flowering completes in 8-10 weeks. Trichome development typically accelerates in weeks 5-6, and the myrcene aroma becomes unmistakable by week 7. Typical indoor yield: 350-450g/mΒ² under LED. Height at harvest: Medium (3-4 ft). Difficulty: intermediate, nothing here that would intimidate a grower with one successful harvest behind them.
The one thing to watch: calcium demand commonly spikes under intense LED light, faster growth under high PPFD can outpace a standard cal-mag dosing schedule.
What Users Report
Purple Arrow at 21% THC produces creative, calm sensations that users consistently describe as physically comforting without being immobilizing at moderate doses. The relaxation builds gradually, noticeable within 10 minutes, settling fully by the 20-minute mark, and sustaining for 2-3 hours. The Myrcene/Humulene terpene pairing gives this strain a distinctive effect signature that experienced users recognize as different from other indicas at similar THC levels.
Best suited for evening use, unwinding after a long day, and situations where deep physical relaxation is the goal.
Terpene Profile
Dominant terpenes: Myrcene (primary), Humulene (secondary), Linalool (tertiary). This combination produces a flavor that rewards patience in the cure, the terpene complexity at week 4 in jars is substantially more interesting than the flat, one-note character of a rushed one-week cure.
Who Should Grow Purple Arrow
This strain fits growers with at least one harvest behind them who want to step up in quality without dramatically increasing complexity. The autoflowering genetics simplify the growing process, no light schedule management, compact size, and a fast seed-to-harvest timeline. Indoor growers in any US state can run this strain with standard tent equipment. Outdoor growers should match the 8-10 weeks flowering period to their frost-free window.
Effects
Best For
Strain Type
Strain Data Sheet
Packaging
Regular
Seeds
authenticity
lining
number
Related Strains

Ancient Kush Feminized
Buy Ancient Kush Feminized cannabis seeds online in the USA. Indica strain with 19% THC. Effects: Relaxed, Sleepy, Happy. Discreet shipping to all 50 states with germination guarantee.

Grape Skunk Feminized
Buy Grape Skunk Feminized cannabis seeds online in the USA. Indica strain with 20% THC. Effects: Euphoric, Creative, Calm. Discreet shipping to all 50 states with germination guarantee.

707 Headband Feminized
Buy 707 Headband Feminized cannabis seeds online in the USA. Sativa strain with 22% THC. Effects: Euphoric, Creative, Uplifted. Discreet shipping to all 50 states with germination guarantee.

Blue Cinex Feminized
Buy Blue Cinex Feminized cannabis seeds online in the USA. Sativa strain with 22% THC. Effects: Euphoric, Creative, Focused. Discreet shipping to all 50 states with germination guarantee.
Purple Arrow Auto, Cannabinoid & Terpene Reference
Reference ranges aggregated from publicly-reported third-party lab data and breeder documentation. Total THC reported as max-potential (THC + 0.877 Γ THCA). Individual seed-lot expression may vary by 1-3 percent.
Purple Arrow Auto, Aggregated Grower Yield Reports
Yield ranges aggregated from public grower journals, breeder-documented spec sheets, and cultivation community reports on Purple Arrow Auto autoflower seeds. First-time growers should expect 70-85 percent of these numbers.
| Setup | Yield |
|---|---|
| 5Γ5 tent, 730W LED, ScrOG | 304g |
| 4Γ4 tent, 600W LED, LST | 304g |
| Outdoor, balcony, 5-gal fabric pot | 418g |
Purple Arrow Auto, Sourcing & Genetics
Purple Arrow Auto was first stabilized in Amsterdam coffee-shop circles in the 2000s and adapted to American growing conditions through North American breeding programs.
Versatile across all US climates, 8-10 week cycle works in any growing window from Maine to Hawaii.
Purple Arrow Auto, Breeder Information
Royal King GeneticsBred and stabilized in-house by Royal King Genetics , our internal breeding team. Every order is backed by our 95% germination guarantee. Read our full breeding process and about page.
Autoflowering genetics need multi-generation fixing because the ruderalis-derived auto trait is recessive. Purple Arrow sits at F5, every plant in the pack autoflowers reliably and finishes within a tight window.
Reach auto trigger and finish-window uniformity for the Purple Arrow pack.
Selected for purple/dark expression where present, dense bud structure, and indica relaxation profile.
Royal King Genetics breeding program, pollen from selected sibling males of the recurrent parent.