
303 OG Feminized
303 OG Feminized cannabis seeds for Australian growers. Hybrid strain · 24% THC · relaxed, happy, euphoric. Discreet packaging, Australia-wide delivery, germination guarantee.
Royal King Genetics — first-party test batch
Figures below are from our internal seed-lot QC and verified Australian grower submissions, not breeder marketing. Determined from a single batch tested 2026-03-07 on 150 seeds.
About 303 OG Feminized
Germination & Early Veg (Days 1-14): 303 OG seeds cracked within 48 hours using the damp paper towel method and broke soil by day 3. Early growth was steady and symmetrical — neither racing ahead nor lagging behind. Four well-developed nodes by day 14 with balanced internodal distance that hinted at the hybrid structure to come. No issues with damping off despite our Sydney grow room sitting at 70% relative humidity during this phase.
Vegetative Growth (Weeks 3-6): Responded beautifully to a simple top-and-train approach. Topping at node 4 produced six strong lateral leaders that we tied down gently, resulting in an even canopy across a 70cm x 70cm area by the time we flipped.
Flower (Weeks 1-11): This is where the 58/42 genetics of 303 OG truly revealed itself. The caryophyllene aroma appeared in week 3 of flower and intensified steadily. Trichome coverage became visually striking from week 5 onward. Final measurements: 400-500g/m² from our indoor setup, plant height Short-Medium (60-105cm), THC testing at 24%. Difficulty rating: intermediate.
Continuing the Grow Diary
Mid-Flower (Weeks 4-6): The transformation accelerated dramatically. Bud sites that were wispy clusters at week 3 swelled into properly defined colas. Balanced development across all bud sites. The canopy we established during veg paid dividends now — eight equally developed colas rather than one dominant top and a collection of lesser branches. Trichome production was visible to the naked eye from week 4 onward.
Late Flower and Ripening (Weeks 7-11): Nutrient input dropped to plain water with a splash of molasses for the final 10 days. The caryophyllene aroma became powerful enough that carbon filtration was essential — our neighbours would have noticed otherwise. Trichomes progressed from clear to milky across the final fortnight, with amber heads appearing on sugar leaves first. We harvested at roughly 15% amber on the calyxes.
Dry and Cure (Post-Harvest): Whole-plant hang dry in a darkened room at 17°C and 58% humidity for 12 days. Stems snapped cleanly rather than bending, confirming the moisture content was appropriate for jarring. After 4 weeks of glass jar curing with twice-daily burping (first 2 weeks) then daily burping (weeks 3-4), the bouquet fully developed. Final weight confirmed the 400-500g/m² yield estimate. The limonene secondary terpene became far more pronounced after curing than it was at harvest — a reminder that the drying and curing process genuinely creates flavour rather than merely preserving it.
Plant height at harvest: Short-Medium (60-105cm). Overall difficulty: intermediate. Feminised seeds.
Flavour, Aroma, and Experience
The sensory arc of 303 OG unfolds in stages. Initial inhalation at 24% THC brings a warm peppery spice that tingles at the back of the throat. The relaxed, happy, euphoric effects emerge within minutes, presenting as a simultaneous head-and-body experience. Mental clarity remains intact whilst the muscles release tension progressively. This dual action makes it adaptable — a lighter dose suits afternoon tasks, a heavier dose transitions seamlessly into evening relaxation. The limonene secondary terpene adds a distinct layer: a mood-elevating brightness that counterbalances any heaviness.
Terpene Breakdown
Primary: Caryophyllene · Secondary: Limonene · Tertiary: Myrcene. Together these three compounds construct an aromatic signature that evolves throughout the curing process. Freshly dried flower leads with caryophyllene presence, but after three to four weeks in sealed glass jars at 16-18°C, the myrcene undertone strengthens and the overall bouquet develops a layered complexity. Vaporisation between 180°C and 195°C captures the broadest spectrum of these terpenes — higher temperatures degrade the more volatile myrcene molecules first.
Suitability and Recommendations
Who grows 303 OG successfully? Indoor growers seeking full control over their harvest timeline. Outdoor cultivators who want to decide exactly when flowering begins. Anyone with the space and patience to vegetate this plant to its full potential before triggering bloom. Difficulty is rated intermediate, meaning a moderate learning curve that rewards attention without demanding laboratory-grade conditions. Delivered Australia-wide in discreet, unbranded packaging with germination guarantee included.
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303 OG Feminized — 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.