
Motorbreath #15 Feminised
Motorbreath #15 Feminised seeds. A hybrid cultivar at 23% THC delivering relaxed, happy, euphoric. Grow figures from named sources.
Royal King Genetics — first-party test batch
Figures below are from our internal seed-lot QC and verified UK grower submissions, not breeder marketing. Determined from a single batch tested 2026-09-08 on 250 seeds.
About Motorbreath #15 Feminised
Germination and early veg, days 1-14. Motorbreath #15 seeds generally crack inside 48 hours on damp kitchen roll and break the surface around day three. Early growth came in even and unhurried, neither racing nor sulking. Four solid nodes by day 14 with the spacing that hints at the hybrid frame to come. Damping off is rare around 70% relative humidity, which is also roughly what an unheated British room sits at in spring.
Veg, weeks 3-6. It took a simple top-and-tie approach well. Topping at node four gave six strong leaders, tied down gently, and an even canopy across a 70cm square by the flip.
Bloom, weeks 1-10. This is where the 62/38 balance in Motorbreath #15 showed itself. The caryophyllene came up in week three and kept building; trichome cover was obvious to the naked eye from week five. Indoor yield: up to 400 g/m2. THC testing at 23%. Rated intermediate.
The rest of the diary
Mid-bloom, weeks 4-6. The change came quickly. Sites that were loose and wispy at week three closed into defined colas. Development stayed even across the whole canopy, which is what the veg training bought — eight comparable colas instead of one dominant top and a handful of also-rans. Resin was visible to the naked eye from week four.
Ripening, weeks 8-10. Feeding dropped to plain water for the last ten days. The caryophyllene got strong enough that carbon filtration stopped being optional in a terraced house. Trichomes ran clear to milky across the final fortnight, amber showing on sugar leaves first. Around 15% amber on the calyxes is a common place to stop.
Drying and curing. Whole plant hung in the dark at 17°C and 58% humidity for twelve days — both numbers held by a dehumidifier, because an October room in this country will not hold either on its own. Stems snapped rather than bent, which is the test worth trusting. Four weeks in glass followed, burped twice daily for the first fortnight and once daily after. Final weight matched the up to 400 g/m2 figure. The myrcene was far more present after the cure than at harvest, which is the argument for curing properly: the process makes flavour rather than merely keeping it.
Flowering: 60-70 days. Indoor yield: up to 400 g/m2. Outdoor yield: up to 400 g/plant. Rated intermediate difficulty. Feminised seeds.
What Motorbreath #15 is actually like
Growers report relaxed, happy, euphoric as the defining characteristics and our own notes agree. At 23% THC this hybrid sits where the balance is the selling point. Taken small it stays functional; taken larger it relaxes properly. The ${indica}/${sativa} split means the direction is set by how much you take rather than fixed by the genetics. The Caryophyllene/Myrcene pairing leaves warmth and spice that dries slightly on the exhale.
Best suited to most occasions — the dose does the steering.
Terpene breakdown
Primary: Caryophyllene · Secondary: Myrcene · Tertiary: Humulene. These three build an aroma that keeps moving through the cure. Fresh off the dry it leads with caryophyllene; after three or four weeks sealed in glass at 16-18°C the humulene underneath comes up and the whole thing gains a layer. Vaporising between 180°C and 195°C catches the widest span of them, since the lighter humulene molecules are the first thing heat destroys.
Who it suits
Motorbreath #15 suits growers with the basics in place. Understand pH, rough nutrient ratios and light cycles before you commit to it; it asks for competence rather than expertise. Photoperiod genetics leave plant size and harvest date under your control — veg longer for bigger plants, or flip early when space is short. The April to October season accommodates a bloom of 60-70 days comfortably for outdoor growers across the country.
Effects
Strain Type
Strain Data Sheet
Packaging
Feminised Premium
Seeds
authenticity
lining
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Motorbreath #15 Feminised — Breeder Information
Royal King GeneticsBred and stabilised in-house by Royal King Genetics — 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.
A newer mid-2010s cross still being actively stabilised. F3 means three rounds of selection — the cross-derived trait balance is locked across the bulk of the pack, with a small variant subset under continued cull.
Cull off-type phenos in Motorbreath #15 at F3 to lock the cross profile.
Chosen for trichome density, bud structure and the hybrid trait balance the cross was engineered for.
Royal King Genetics in-house mother stock — pollen taken from a sibling male drawn from the same selected pheno population.