
Blue Diamond Feminised
Grow Blue Diamond Feminised in the UK. Sativa genetics at 22% THC, known for euphoric, creative, calm effects.
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 2026-09-13 on 100 seeds.
About Blue Diamond Feminised
Will Blue Diamond finish outdoors in Britain? Yes, within the April to October season. Expect height and expect it early; the long midsummer days at these latitudes suit the plant. Give it room to stretch and tie it down rather than fighting it. Flowering runs 50-60 days, which puts harvest in September or October for most of the country.
What yield is realistic? up to 400 g/m2 indoors is achievable with competent LED lighting and attention to feeding. Outdoors, up to 400 g/plant is realistic in 50 litre pots or in prepared ground with full sun — and "full sun" is doing a lot of work in that sentence at these latitudes, so the position you pick in the garden matters more than the pot you buy. At 22% THC with a pinene-forward profile, the return on the effort is sound.
Is it forgiving? Reasonably. Anyone comfortable with pH, a feed schedule and a light timer will get a good result. It will not hold your hand, but it will not punish one missed watering either.
Further questions we get asked about Blue Diamond
Which medium? For flavour, peat-free soil cut with about 30% perlite and amended slowly — fish, blood and bone, rock phosphate, seaweed meal, all of it available at any British garden centre. For weight, coco with fertigation at EC 1.4-1.8 through bloom. This sativa performs in both; the choice is about what you want out of it.
How does it handle a British summer? Better than most, because the open structure lets heat out. In a genuine heatwave you may see midday droop, with recovery by evening. Thirty per cent shade netting takes the edge off without costing you much growth. The more common British problem is the opposite one: a cold, wet July that never lets the plant dry out between waterings.
When do I switch to bloom feed? Inside the first week of visible pistils. The 14/86 balance shifts its demand quickly at the transition — phosphorus and potassium up, nitrogen down. Soil growers can top-dress with guano and sulphate of potash; coco and hydro should move to a low-nitrogen bloom formula straight away.
Indoors or outdoors? Both work, for different reasons. Indoors you own the flowering environment completely. Outdoors, across the April to October season, the plant gets a light intensity no domestic LED matches and can reach up to 400 g/plant — at the price of accepting whatever the autumn does. Flowering: 50-60 days. Indoor yield: up to 400 g/m2. Outdoor yield: up to 400 g/plant. Rated intermediate difficulty.
Flavour, aroma and effect
Blue Diamond arrives in stages. The first draw at 22% THC brings clean resin, like woodland after rain. The euphoric, creative, calm character follows within minutes, arriving as sharpened attention. Colour reads brighter, music reads busier, and conversation wanders further than it would otherwise. It holds for two to three hours on a plateau rather than a spike. The limonene underneath adds a lift that stops it turning heavy.
Terpene breakdown
Primary: Pinene · Secondary: Limonene · Tertiary: Caryophyllene. These three build an aroma that keeps moving through the cure. Fresh off the dry it leads with pinene; after three or four weeks sealed in glass at 16-18°C the caryophyllene 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 caryophyllene molecules are the first thing heat destroys.
Who it suits
Who does well with Blue Diamond? Indoor growers who want the timeline under their own control. Outdoor growers who want to choose when flowering starts. Anyone with the room and the patience to veg it properly before flipping. Difficulty is rated intermediate, which means a moderate learning curve that rewards attention without demanding a laboratory.
Effects
Strain Type
Strain Data Sheet
Packaging
Feminised Premium
Seeds
authenticity
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Blue Diamond 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.
F3 stabilisation on the Blue Diamond cross. Three rounds of selection have brought the population to roughly 80% trait homogeneity — a small fraction of pheno variance is still present and is being culled in the next cycle.
Stabilise Blue Diamond across three rounds toward F4 production-ready stock.
Chosen for terpene saturation, sativa vigour and a workable finish time despite long-flowering genetics.
Royal King Genetics in-house breeder room — pollen taken from a generation-tracked sibling-male line.