Magnum Strain — Effects, Genetics, Grow Guide & Where to Buy
Among the strains American growers consistently come back to, Magnum sits near the top of the list, with a profile that holds up under scrutiny. It is a balanced hybrid (49% indica / 51% sativa) testing at roughly 15% THC, with a flowering window of 8-10 weeks under a 12/12 photoperiod. On this page we cover the effects, the lineage, the grow profile, and where to buy Magnum seeds in the United States with discreet shipping and a 95% germination guarantee.
Magnum Quick Stats
THC
15%
Indica
49%
Sativa
51%
Autoflower
No
Flowering
8-10 weeks
Difficulty
intermediate
Indoor Yield
450-550 g/m²
Outdoor Yield
500-700 g/plant
Plant Height
120-180 cm
Magnum Effects & Experience
The dominant effects of Magnum are focused, calm, and the experience is more nuanced than a simple high/low/sedating label would suggest. Onset is gradual rather than abrupt, the peak holds for roughly an hour, and the comedown is smooth — which is why this strain shows up in so many "daily driver" lists from experienced consumers.
Growing Magnum
Growing Magnum fits indoor tent growers running standard 4x4 setups; the hybrid frame responds well to topping and LST. Magnum is photoperiod, which means you control when it flowers by switching from 18/6 (vegetative) to 12/12 (flowering). Most indoor growers veg for 4-6 weeks before the flip. Indoor yields land around 450-550 g/m² under quality LED, and outdoor plants given full sun and 5-7 gallon containers reliably produce 500-700 g/plant. Expected plant height is 120-180 cm, with intermediate cultivation difficulty. Practical tips that move the needle: flush nutrients in the final 10-14 days for cleaner flavor; trichomes finish properly even on plain pH-adjusted water; and feed cal-mag from week 2 onward at 2-3 mL per gallon — most reverse-osmosis and soft tap water setups need it. The most common challenge growers report is over-feeding nitrogen past week 1 of flower — switch to bloom nutrients within 7 days of seeing pistils.
Magnum Lineage & Genetics
Magnum is a Royal King Genetics in-house cross. The parental selection was chosen for hybrid vigor and a balanced effect profile, then stabilized over multiple generations to lock in phenotype expression. Seeds run true to the description on this page rather than spreading across a wide range of expressions.
Where to Buy Magnum Seeds in the USA
Magnum seeds ship from Royal King Seeds to all 50 US states with discreet packaging and a 95% germination guarantee. Average delivery is 3-5 business days, with the fastest routes typically reaching Alaska, Arizona, Arkansas, California, Colorado.
Magnum FAQ
Is Magnum indica or sativa?+
Magnum is a balanced hybrid with a 49% indica / 51% sativa split. The effects lean balanced — neither dominantly head nor body.
How long does Magnum take to flower?+
Magnum flowers in 8-10 weeks once you flip to 12/12 light cycle. Outdoor harvest typically lands in late September to mid-October across most US zones.
What is the THC content of Magnum?+
Magnum tests at approximately 15% THC when grown to its potential. Real-world numbers depend on grow conditions, harvest timing, and curing — well-grown phenotypes can land at the high end of that range, while poorly cured flower tests lower.
Is Magnum good for beginner growers?+
Magnum is rated intermediate difficulty. Photoperiod genetics give you control over plant size and harvest timing, which means a bit more responsibility for getting the schedule right. Most growers with one harvest behind them handle this strain without difficulty.
Where can I buy Magnum seeds in the USA?+
Royal King Seeds ships Magnum seeds to all 50 US states with discreet packaging, 3-5 day delivery, and a 95% germination guarantee. The product page is at https://royalkingseeds.us/magnum-feminized — checkout accepts standard cards, Apple Pay, and crypto.