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Serious 6 strain

Serious 6 Strain Created by Serious Seeds

F1-hybrid, almost pure Sativa

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Serious 6 was created as an almost pure Sativa with a very short flowering time by mixing genetics from Canada with Sativa-landraces from Africa. She is vigorous, very mold-resistant and will finish VERY EARLY outdoors, from the middle to end of September, even in a humid and cold climate. 
Recommended veg.
2 - 3 weeks
Indoor flowering
8 weeks (only for outdoor)
Indoor yield
500 - 1000 gram per plant
Outdoor harvest
mid/late September
THC level
CBD level
€ 50,00

Pack size

Strain Description

The result of a selection work, research, and crossing for optimized genetic characteristics! 

Flowering INDOORS is ONLY recommended to EXPERT growers, as a tiny portion of the plants can have hermaphroditic tendencies (2 out of 100 plants are stress-sensitive to light stress). Outdoors under natural light that is no problem, Serious 6 grows tall and slender with full buds, only a few small leaves and a particularly thick layer of crystals.


The genetics of Serious 6 is a long work of selection and crossing between local African sativa varieties and Canadian genetics.

Taste and Aroma: 

The aroma of Serious 6 buds is extremely complex: lemony, aniseed, fresh and spicy, are just a few of the recognizable flavors! Serious 6 will delight terpene hunters! 

Its Cultivation:

 Outdoors, Serious 6 cannabis plants are ready to be harvested even in northern climates by the end of September at the latest. Serious 6 grows tall, with full flowers and low foliage. Throughout the flowering of Serious 6, an extremely thick layer of resin crystals forms. About half of the plants display beautiful pink flower pistils. Serious 6 also has pink hues  during growth, which are replaced by purple tones in the flowers and leaves towards the end of the flowering period.

Its Effects:

Serious 6 has fundamentally a moderately strong effect on the Mind (a little bit Activating or Creative  and also a hint of Thoughtful or meditative) in short: a crystalline high in the head that activates and makes you creative, but also affects physically a bit.

In a few numbers:

Flowering period: 53  days or 8 weeks 

harvest potential: between 350 and 500 g/M2

In a few words:

Serious 6 is a very mold-resistant and very early outdoor variety, finishing in September in a humid and cold climate. The plant, with thin stems, grows tall, with well-filled heads under a very thick layer of crystals. Half of the plants have very pretty pink pistils, some plants have purple hues. Serious 6, an almost pure Sativa variety, has a very short flowering time (8 weeks) and a surprising yield indoors. Long and dense heads shiny with trichomes (hairs) of an aroma in different layers: lemon, anise, spices, and others. A clear as crystal water, active, and creative cerebral effect. Serious 6 finished 2nd at the Higlife Cup 2013 in Amsterdam, in the BIO-Weed category.

A bit of history:

-At the Spannabis Fair 2013, an indoor bud was tested in the CANNA laboratory and had the highest measured value of all herb varieties that day with 17% THC!

Serious 7 - Additional Information:

We have been working for years to improve Serious 6. Not so easy. Now, we have something that might be interesting for people. Serious 7: a more uniform plant than Serious 6 in all respects. The harvest date of Serious 7 is generally more similar to the older Serious 6. A bit less smelly than Serious 6, which is good against neighbors. More crystals make it a bit stronger and no pink pistils. Losing the pink colors is not what we wanted, but in breeding, one has to make choices and compromises. The pink colors of Serious 6 are beautiful as long as the plant is alive. The dried buds no longer have a pink color anyway. Serious 7 is a rewarding variety. One could say it's the white pheno of Serious 6. We are not (yet) selling this variety, but we give it as a promotional seed to get feedback from you. Tell us what you think of Serious 7. If enough people like it, we will probably put it on our menu.

Strain Reviews

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4.77 / 5 out of 13 ratings

13 Reviews

Michiel H.Verified buyer

Ik heb nu 3 jaar serious 6 in m in achtertuin gegroeid, telkens 5 planten.
Ik vind het een verrassend makkelijk soort om buiten te groeien. Ze staan in 30 liter potten en heb nog geen één keer minder als 200 gram geknipt en gedroogd per plant geoogst, met uitschieters tot 350 gram.
Met haar mooie roze toppen misstaan ze ook niet in de tuin.
Ze is heerlijk te roken en geeft een goede high.
Ik ga dit jaar grotere potten gebruiken, kijken wat dat met de opbrengst doet.

CaptainVerified buyer
serious six amazing

I grow in South Western Ontario, Canada.
Easy to grow, big yields, beautiful colors, nice taste, early finish, first of September to mid Sept.
Had this strain Analyzed, THC 20.43%... CBD 0.03%... CBN 0.06%
Nice clear daytime high, makes great bubble hash

the c.Verified buyer
Fast finishing sativa with beautiful flowers and uplifting high

First of all I want to thank customer service. I bought a pack of S6 seeds in Amsterdam, but for whatever reason none of them germinated. I contacted Serious seeds and they sent me a new pack for free. All of them germinated and gave me beautiful flowers by late September outdoors in a Mediterranian climate.The effect was as expected uplifting and inspiring. Definetely growing Serious 6 again.

Cephas L.Verified buyer
Serious 6 Feminised

I have grown seroius six for the two prevoius seasons and this will be my third. Seroius six is definitely the earliest mould resistant and strain I have found so far, and i have been growing outdoors on the western wet side of an island near holland at 50 degrees north for almost 20 years. I have been looking for something decent since Paradise seeds discontinued "Rox" about 12 years ago.(was a horrible smoke anyway) "Frisian dew" was ok but a lacklustre smoke and not mold resistant enough. "Leda uno" was an ok smoke and very mould resistant but way too late. I have been very happy with seroius six on all counts especially the first year when I got a pheno that finished in early september with a lovely skunky flavour. (Not as mould resistant as the main phenotype tho). Generally the cropping is started by 20 sept and completely in by 10 oct being cropped in two stages to let the lower buds mature more. It could have been left longer as there was virtually no mould (i think i found two tiny spots in the whole lot), The calyxes were fully mature. Yield wise i am getting about 100g/plant but watering is limited due to guerilla growing tactics. I would expect a lot more if i could grow it in my garden. Smoke wise it is a nicely flavoured clean heady sativa leaving almost no negative after effects. I know they are some of the more expensive seeds out there but you get what you pay for and if you are going to spend all summer looking after them it is well worth the investment. Thank you Serious Seeds

Stuart B.Verified buyer
Great as always still the

Great as always still the best..:)