
303 OG Feminised
303 OG Feminised cannabis seeds for Irish growers. Hybrid strain · 24% THC · relaxed, happy, euphoric. Discreet packaging, nationwide delivery, sourced grow figures.
Royal King Genetics — 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 2026-09-10 on 500 seeds at 21-24°C.
About 303 OG Feminised
Days 1-14, germination and early veg. 303 OG generally cracks within about two days on damp kitchen paper and is above the medium by day three. The first fortnight came in even, without either racing or stalling. Four solid nodes by day 14 and the spacing that suggests the frame it will build. Keep the humidity near 70% and damping off stops being a concern.
Weeks 3-6, veg. A top at node four and a few ties produced six even leaders and a flat canopy across a 70cm square by the time it was flipped.
Bloom, weeks 1-10. The 58/42 character came through clearly. Caryophyllene was noticeable by week three and kept building; resin was obvious without a loupe from about week five. Indoor yield: up to 300 g/m2. Height: Short. Tested at 24%. Rated easy.
The rest of the run
Weeks 4-6, mid-bloom. Loose clusters from week three closed up into defined colas. Development stayed even across the canopy, which is what the veg training was for: eight comparable colas instead of one dominant top and a set of stragglers.
Ripening, weeks 8-10. Plain water for the last ten days. Caryophyllene was strong enough by then that carbon filtration was not optional in a terraced house. Heads went clear to milky over the final fortnight, amber showing on sugar leaves first, and around 15% amber on the calyxes is a defensible place to stop.
Drying and curing. Hung whole in the dark at 17°C and 58% humidity for twelve days, both held by a dehumidifier because an October room here will hold neither. Stems snapped instead of bending, which is the only test worth trusting. Four weeks in glass after that. The up to 300 g/m2 figure held up. Limonene was far more present after the cure than at harvest — the cure makes flavour, it does not merely preserve it.
Flowering: 60-70 days. Indoor yield: up to 300 g/m2. Outdoor yield: up to 350 g/plant. Plant height: Short. Rated easy difficulty. Feminised seeds.
Flavour, aroma and effect
303 OG arrives in order. The first draw at 24% THC gives peppercorn heat that lands at the back of the throat. The relaxed, happy, euphoric character follows in minutes, as head and body together. Thinking stays clear while the muscles let go by degrees, which is what makes the dose, rather than the genetics, the thing that decides the evening. Limonene underneath contributes a lift that stops it going heavy.
Terpene breakdown
Primary: Caryophyllene · Secondary: Limonene · Tertiary: Myrcene. The three shift relative to each other across the cure. Straight off the dry the caryophyllene dominates; three or four weeks sealed in glass at 16-18°C and the myrcene underneath comes up to meet it. Vaporising between 180°C and 195°C catches the widest span, because heat takes the lighter myrcene molecules first.
Who it suits
Who does well with 303 OG? Indoor growers who want to choose their own timeline. Tunnel growers who want to decide when flowering starts rather than letting August decide it. Anyone with the space to veg it properly first. Rated easy, which means a moderate learning curve that rewards attention without needing specialist kit.
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303 OG 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.
BX3 is the credible stabilisation point for a clone-only 2010s production cultivar. We worked 303 OG through three backcross generations to recreate the elite cut in seed form. A sibling male pollinates the mother each cycle to drive trait fixation.
Pin the trichome production of the elite cut into the population.
Chosen for trichome density, bud structure and the hybrid trait balance the cross was engineered for.
Royal King Genetics breeding facility — pollen from internally selected sibling males of the recurrent parent.