YumboldtStrain, Effects, Genetics, Grow Guide & Where to Buy
Few cultivars carry the cult following Yumboldt has built across the US grow community , and the appeal is easy to explain. It is a indica-dominant (71% indica / 29% sativa) testing at roughly 15% THC, with a flowering window of 50-60 days as an autoflower. What follows is a complete reference: terpene-led effects, genetic background, indoor and outdoor grow guidance, and the fastest way to get Yumboldt seeds shipped to your state.
Yumboldt Quick Stats
THC
15%
Indica
71%
Sativa
29%
Autoflower
Yes
Flowering
50-60 days
Difficulty
intermediate
Indoor Yield
up to 300 g/m2
Outdoor Yield
up to 350 g/plant
Plant Height
Short
YumboldtEffects & Experience
Yumboldt is best known for relaxed, sleepy, happy. The effects come on within the first 10 minutes and settle into a stable plateau that lasts 90 minutes to two hours at typical doses. Growers and users consistently note that the high stays true to its profile rather than drifting, what you feel in the first 20 minutes is what you have for the next 90.
Growing Yumboldt
Growing Yumboldt fits cooler climates where photoperiod strains struggle to finish before frost, autoflower timing is calendar-driven, not daylight-driven. Yumboldt runs on an 18/6 light schedule from seed to harvest, autoflower genetics ignore photoperiod, so there is no flip and no light-cycle change. Indoor yields land around up to 300 g/m2 under quality LED, and outdoor plants given full sun and 5-7 gallon containers reliably produce up to 350 g/plant. Expected plant height is Short, with intermediate cultivation difficulty. Practical tips that move the needle: feed cal-mag from week 2 onward at 2-3 mL per gallon, most reverse-osmosis and soft tap water setups need it; and maintain canopy airflow with an oscillating fan moving air through the leaves, not just above them, to prevent powdery mildew. The most common challenge growers report is training timing, top at the 4th node, not earlier and not later, for the best canopy distribution.
YumboldtLineage & Genetics
This cultivar is part of the Royal King Seeds curated catalog. Read the description as a general profile rather than a guarantee of your specific pack.
Where to Buy Yumboldt Seeds in the USA
Yumboldt seeds ship from Royal King Seeds from within the United States. Estimated delivery is approximately 5-7 business days; actual timing varies by destination and carrier.
Yumboldt FAQ
Is Yumboldt indica or sativa?+
Yumboldt is a indica-dominant with a 71% indica / 29% sativa split. The effects lean toward physical relaxation and a calm, settled headspace.
How long does Yumboldt take to flower?+
Yumboldt flowers in 50-60 days from seed, since autoflower genetics ignore light cycle. Outdoor harvest typically lands 70-90 days after planting.
What is the THC content of Yumboldt?+
Yumboldt 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 Yumboldt good for beginner growers?+
Yumboldt is rated intermediate difficulty. The autoflower genetics simplify the process, no light schedule changes and a fast seed-to-harvest timeline make it forgiving for first-time growers. Most growers with one harvest behind them handle this strain without difficulty.
Where can I buy Yumboldt seeds in the USA?+
Royal King Seeds ships Yumboldt seeds from within the United States, with estimated delivery in approximately 5-7 business days. The product page is at https://royalkingseeds.us/yumboldt-auto.