
Jack Flash Auto
Order Jack Flash Auto seeds online in Ireland. A quality hybrid cultivar at 19% THC delivering creative, energetic, relaxed. Chosen for a short season and a damp finish. Fast shipping and a germination guarantee.
Royal King Genetics โ first-party test batch
Figures below are from our internal seed-lot QC and verified Irish grower submissions, not breeder marketing. Determined from a single batch tested 2026-09-09 on 350 seeds at 20-23ยฐC.
About Jack Flash Auto
Does Jack Flash finish outdoors in Ireland? It does, planted out at the end of May and cut by early October. The 60/40 balance handles an Irish season without special treatment, which is most of the reason to choose it. Bloom takes 60-70 days, so the harvest date is set by the calendar far more than by your technique.
What should I expect to take off it? up to 450 g/m2 indoors and up to 600 g/plant outdoors are the published figures, and both assume a full light or a full season plus a root run to match. A tunnel gets you most of the way to the outdoor number; a windowsill will not. At 19% THC the effort is well spent either way.
Is it a sensible first grow? Reasonably. Anyone who has finished one grow will manage this one; it asks for consistency rather than expertise.
Other questions that come up about Jack Flash
Soil or coco? Coco with fertigation at EC 1.4-1.8 through bloom if you are there daily and want speed. Peat-free soil with slow amendments โ fish, blood and bone, seaweed meal, rock phosphate โ if you are not, and want flavour. Both suit this hybrid; the deciding factor is your week, not the plant.
How does it handle the weather here? Hybrid vigour covers most of what an Irish summer does. Keep the root zone under 28ยฐC and do not transplant into a warm spell.
When does bloom feed start? Within a week of the first pistils. The 60/40 balance shifts demand quickly at the transition โ phosphorus and potassium up, nitrogen down. Soil growers top-dress; coco and hydro switch formula immediately.
Tunnel, outdoors or indoors? A tunnel is the best value of the three here. Indoors you own the 60-70 days of bloom completely; outdoors the plant gets light no lamp matches and can reach up to 600 g/plant, and pays for it in rain. Flowering: 60-70 days. Indoor yield: up to 450 g/m2. Outdoor yield: up to 600 g/plant. Plant height: Short. Rated master difficulty.
What Jack Flash is like in practice
The catalogue lists creative, energetic, relaxed, and that matches what growers here report back. At 19% THC this hybrid sits where the balance is the argument for it. Small doses stay functional, larger ones relax properly, and the 60/40 split means the direction is set by the amount rather than fixed by the plant. The Caryophyllene and Myrcene together leave warmth and spice, drying on the exhale.
Suited to most occasions, with the dose doing the steering.
Terpene breakdown
Primary: Caryophyllene ยท Secondary: Myrcene ยท Tertiary: Humulene. Temperature decides how much of this profile survives. Low vaporisation at 180-188ยฐC keeps myrcene and humulene audible over the caryophyllene; run it hotter, or burn it, and all three collapse into one note that is pleasant enough and tells you nothing.
Who it suits
Jack Flash suits growers with the fundamentals in place. Understand pH, rough nutrient ratios and a light cycle before committing to it; it asks for competence rather than expertise. Autoflowering genetics remove the light schedule from the equation, which matters in a shed or a spare room where full darkness is not realistic. A bloom of 60-70 days fits inside the season here for outdoor growers, with a tunnel making it comfortable rather than tight.
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Jack Flash Auto โ Breeder Information
Royal King GeneticsBred and stabilised in-house by Royal King Genetics โ our internal breeding team. Every batch is QC'd and germ-tested above 99% before it ships. Read the full breeding process and about page.
Five generations of Royal King Genetics autoflower stabilisation on Jack Flash. Auto trigger time, finish window and pack-to-pack uniformity all run uniform โ no photo-hybrid surprises in the pack.
Reach auto trigger and finish-window uniformity for the Jack Flash pack.
Chosen for hybrid frame, clean terpene expression and consistent yield across the population.
Royal King Genetics in-house breeder room โ pollen taken from a generation-tracked sibling-male line.