Opium cannabis seeds packaging — Royal King Seeds the UK
Hybrid
THC 21%
📈 High Yield
HybridFeminizedIn Stock

Opium Feminized

Feminized PhotoperiodSee Lab Report →

Opium Feminized seeds. A hybrid cultivar at 21% THC delivering euphoric, calm. Grow figures from named sources.

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About Opium Feminized

Can I grow Opium outdoors in the UK? Absolutely. This 62/38 hybrid is well-suited to the UK outdoor season running April through October. The balanced genetics handle UK conditions reliably, adapting to everything from damp coastal air to the drier east of the country. Flowering takes 8-9 weeks, placing your harvest window squarely in September or October for most UK latitudes.

What kind of yield should I realistically expect? Indoor growers pulling 400-450 g/m2 is achievable with decent LED lighting and attentive feeding. Outdoors, 1000 g/plant per plant is realistic in 50+ litre pots or directly in prepared garden soil with full sun exposure. At 21% THC and a myrcene-forward terpene profile, the quality-to-effort ratio makes Opium genuinely worthwhile.

Is this strain forgiving for newer growers? Reasonably so. A grower with basic knowledge of pH, feeding schedules, and light cycles will manage fine. It is not the most forgiving plant if you neglect it entirely, but it will not collapse at the first missed watering either.

More Questions UK Growers Ask About Opium

What growing medium works best for this strain? For maximum flavour complexity, organic soil blended with 30% perlite and enriched with slow-release amendments (blood, fish and bone, rock phosphate, kelp meal — all readily available at a garden centre or your local hydroponics shop). For maximum yield, coco coir with automated fertigation at EC 1.4-1.8 during bloom. Both approaches produce excellent results with this hybrid genetics.

How does it handle British summer heat? Handles heat reasonably well thanks to the hybrid vigour. Keep root zone temperatures below 28°C with mulch or light-coloured pots, and avoid transplanting during heatwave conditions.

When should I start feeding bloom nutrients? Within the first week of visible pistil formation. This cultivar's 62/38 genetics shifts its nutritional demand rapidly at the transition. Phosphorus and potassium uptake increases noticeably, whilst nitrogen demand drops. An organic top-dress of bat guano and sulphate of potash works well for soil growers; hydro and coco growers should switch to a bloom-ratio formula (low N, high PK) immediately.

Indoor or outdoor — which is better for this strain? Both work. Indoor gives you control over the 8-9 weeks environment. Outdoor in the UK growing season (April-October) lets the plant reach its full 1000 g/plant potential with natural sunlight intensity that even expensive LEDs struggle to match. Flowering: 8-9 weeks. Indoor yield: 400-450 g/m2. Outdoor yield: 1000 g/plant. Plant height: <100 cm. Rated intermediate difficulty.

What to Expect When Using Opium

UK customers report euphoric, calm as the defining characteristics, and our experience aligns with that consensus. At 21% THC, this hybrid sits in a potency bracket where versatility is the main advantage. Morning users report functional clarity at lower doses. Evening users report satisfying relaxation at higher doses. The ${indica}/${sativa} balance means the dominant effect direction shifts with consumption amount rather than being locked into a single character. The Myrcene/Limonene terpene combination imparts a flavour that lingers on the palate — earthy and slightly sweet with a fruit-like finish.

Ideal settings: adaptable across occasions — adjust dose to match the energy level your situation calls for.

Terpene Breakdown

Primary: Myrcene · Secondary: Limonene · Tertiary: Pinene. Flavour translation from flower to vapour and smoke differs with this terpene combination. Low-temperature vaporisation (180-188°C) highlights the limonene and pinene notes whilst keeping myrcene as a foundation. Higher temperatures or combustion flatten the profile into a single-note experience — still pleasant, but lacking the complexity that makes this cultivar genuinely interesting to those who appreciate flavour.

Suitability and Recommendations

Opium suits growers with fundamental skills already established. You should understand pH management, basic nutrient ratios, and light cycle requirements before committing to this cultivar — it will not hold your hand, but it will not punish minor mistakes harshly either. Photoperiod genetics give you complete control over plant size and harvest timing — extend the vegetative phase for larger plants or flip early for a quicker turnaround in compact spaces. The UK growing season (April through October) accommodates the 8-9 weeks bloom period comfortably for outdoor cultivators across the country. Shipped discreetly across the UK with our germination guarantee.

Effects

🤗Euphoric
74% of people reported feeling Euphoric
🧘Calm
67% of people reported feeling Calm
😌Relaxed
58% of people reported feeling Relaxed
😊Happy
51% of people reported feeling Happy
🤩Creative
50% of people reported feeling Creative
😎Uplifted
38% of people reported feeling Uplifted
🤤Hungry
34% of people reported feeling Hungry
😴Sleepy
31% of people reported feeling Sleepy
😆Giggly
24% of people reported feeling Giggly

Strain Type

Indica 62%Sativa 38%

Strain Data Sheet

🧬THC21% - 24% (High)
🌿LineageWhite Widow × Durban Poison × Jack Herer
🔬TypeFeminized Hybrid
🌡ClimateTemperate, adaptable
📅HarvestLate Sept – Oct, UK outdoor (typical)
📏Height<100 cm
⚖️YieldMedium – High
🏠Yield Indoor400-450 g/m2
🌳Yield Outdoor1000 g/plant
Flowering Time8-9 weeks

Packaging

Resealable +
RK
Royal King Seeds
Photoperiod
Feminized Premium
Seeds
Premium Genetics
Protective vial
Resealable +
Royal King Seeds supplies seeds as adult novelty collectibles and for genetic preservation. Purchasers must comply with all applicable UK Commonwealth, state, and territory legislation.
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Opium Feminized
royalkingseeds.co.uk
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💧Waterproof coating
🛡️Aluminium interior lining
🏷️Protective sticker
📱QR code verification
🔢Scratchable serial number

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Opium Feminized — Breeder Information

Royal King Genetics

Bred 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.

Stabilisation Level
F4
Generations
4+
Breeding Programme
Royal King Genetics Filial Programme — four-generation pheno fixing
Stabilisation Notes — What This Means for Your Grow

A mid-2010s cross stabilised over four generations of selection. Opium grows true-to-type with the cross-derived trait balance that defines the cultivar.

Breeding Goal

Cull off-type phenos in Opium through filial selection.

Selection Focus

Chosen for trichome density, bud structure and the hybrid trait balance the cross was engineered for.

Pollen / Mother Source

Royal King Genetics in-house breeder room — pollen taken from a generation-tracked sibling-male line.

Last Batch QC Verified
21 May 2026· 99%+ germination