• -50%

BCN Critical XXL© Autoflower Cannabis Seeds

(Kritikal Bilbo X Critical Mas) X Auto Critical Mas

Choose your pack
Pack: 3
  • 1 Seed
    7.50€
    3.75€
  • 3 Seeds
    15.00€
    7.50€
  • 5 Seeds
    22.50€
    11.25€
  • 25 Seeds
    79.00€
    39.50€

Units

-
+
€15.00
€7.50 Save 50%
Tax included

Life cycle: 11 weeks
Grow type: Indoor/Outdoor
Dominant: Hybrid
Yield: Huge
THC: Medium (14 -22%)
Flavor: Citrus Spicy
Effect: Happy Chill
Experience: Beginner

BCN Critical XXL Autoflower

We present BCN Critical XXL© Autoflower, the autoflowering version of one of the most successful strains in the Seedstockers catalogue. No wonder she's worshipped by all types of growers, as she showcases all the properties anyone could wish for in an automatic: she's a fast, vigorous and hardy plant with an out-of-this-world yielding potential and an incredible aroma and flavour. Few genetics are so complete and easy to grow, which has earned her the status of a classic that never disappoints.

Details of BCN Critical XXL© Autoflower Cannabis Seeds

Life cycle 11 weeks
Grow type Indoor/Outdoor
Dominant Hybrid
Yield Huge
THC Medium (14 -22%)
Flavor Citrus Spicy
Effect Happy Chill
Genetica (Kritikal Bilbo X Critical Mas) X Auto Critical Mas
Experience Beginner
  • Uplifting happy high
  • A Seedstockers classic!
  • Perfect for all growers

BCN Critical XXL© Autoflower genetics: Kritikal Bilbo × Critical Mass × Critical Mass Auto

(Kritikal Bilbo X Critical Mass) X Critical Mass Auto → BCN Critical XXL© Autoflower

When it comes to appreciating the benefits of the Critical family, there's no one like Mediterranean growers. And it's precisely here, in Barcelona, that we created one of the greatest successes of our catalogue: BCN Critical XXL© Feminized, the most resistant and productive feminized version of this lineage ever created. BCN Critical XXL© Autoflower keeps the same powers as her photoperiod sister, but she's been designed for growers looking for a cannabis strain that's faster and easier to grow.

Our team of breeders created this "made in Barcelona" strain by combining two legendary genetics, both from the Basque Country:

  • Kritikal Bilbo: brings a sweet, citrusy aroma and lightning-fast flowering.
  • Critical Mass: also known as "Critical+", contributes structure and yield.
  • Critical Mass Auto: gives her the autoflowering character.

The result is a perfect sativa/indica balance, with extremely vigorous growth of around 11 weeks from seed to harvest. And the judges have recognised her too: 1st place for Best Plant at IPM 2026 (Essen). Discover all our cup-winning cannabis strains.

Besides the autoflower version, BCN Critical XXL© also comes as a Feminized and a Fast Version, and she's part of our Critical seed family.

BCN Critical XXL© Autoflower aroma and flavour: skunk, lemon and sweetness

CitrusSpicyLemonSkunkEarthy

FLAVOUR

The intense citrus nuances of the Critical family come with a curious halo of sweet and earthy touches. The result is a dense, compact smoke that's also soft and tasty, ending with a lemon aftertaste that brings freshness to every puff.

AROMA

Her pungent Skunk and lemon aroma, the hallmark of BCN Critical XXL©, has been successfully kept in this automatic version. Her myrcene-dominant terpene profile gives her an earthy, musky and spicy background, with the lemony touch of pinene and limonene.

BCN Critical XXL© Autoflower effects and THC: controlled potency

BCN Critical XXL© Autoflower is characterised by her high psychoactive load, with THC levels that can reach up to 22%. Her powerful effect begins with a very happy and pleasant cerebral high that progressively turns into a soft, long-lasting sensation of bodily relaxation. She's a very balanced strain, cheerful and comforting in equal measure, perfect for moments of relaxation.

BCN Critical XXL© Autoflower FAQ

How long does BCN Critical XXL© Autoflower take from seed to harvest?

Around 11 weeks from germination, with a flowering period of just two months.

What light schedule does she need indoors?

You can use 18 hours of light and 6 of darkness throughout her whole life cycle, although a 20-hour photoperiod is recommended to maximise growth and flowering. Going all the way to 24 hours isn't advised: a short break of darkness helps prevent unnecessary stress.

What pH does she need?

In soil, between 6.0 and 7.0; in hydroponic systems, between 5.5 and 6.5. You don't need an exact figure: an average between 5.5 and 6.5 is fine for her.

Is she good for beginners?

Yes. She's robust, reliable and highly resistant to mould and pests, so she forgives the mistakes of novice growers. Thanks to her short cycle, she's also less vulnerable to spider mites, thrips or powdery mildew.

How to grow BCN Critical XXL© Autoflower indoors and outdoors

When growing indoors, use an aerated substrate and 18-litre pots, and place the germinated seeds straight into their final pot: with such a short cycle, it's best to avoid the stress of transplanting. Although she's slightly indica-dominant, with a branchy, bushy structure and short internodes, she stretches like a sativa during flowering: give her vertical space, as she can grow over one metre tall. This stretch means she handles training techniques well, which is unusual for an automatic.

When growing outdoors she's perfect for warm, dry and temperate climates like the Mediterranean, and a great option for a greenhouse in colder regions. She flowers regardless of the hours of light: germinate in late March or early April and you'll harvest around 11 weeks later, with enough time for several grows in the same season. If you only do one, make the most of the long days of June. Her size makes her ideal for discreet balconies and gardens, and light pollution from a street lamp won't affect her.

Tips to get the most out of her:

  • Watering: in the first few weeks, water sparingly but frequently. Avoid a waterlogged substrate, which can stall her growth.
  • Nutrients: she doesn't need large amounts. It's easier to fix a deficit than an excess of fertiliser.
  • Odour: use activated carbon filters, as her Skunk and citrus fragrance is very intense.
  • Extracts: as a very resinous strain, she's a great candidate for extracts.

Is she the right choice for you?

✅ YES, if you're looking for...

  • A fast automatic: from seed to harvest in around 11 weeks
  • An XXL yield of compact, resinous buds
  • The classic Critical, Skunk and lemon aroma
  • A hardy strain that forgives mistakes
  • Several harvests in the same outdoor season

❌ NO, if...

1st Best Plant
IPM

White Cup

Free shipping on orders above €65 USAFlag

100% Germination Guarantee

Pay with:  com-it-es-payment.png

4.5 rating 36 Reviews
What other growers say about BCN Critical XXL© Autoflower Cannabis Seeds

DID YOU ENJOY YOUR EXPERIENCE WITH THIS VARIETY? LET US KNOW

rating
Submit
Gravy
rating
30/12/2025
Mr

Only 4 weeks in and I'm already super happy with my purchase. Seeds popped after a day or 2 and are growing beautifully, dense short and pretty. No aroma so far, looking forward to the next few months. Will buy again for sure.

Jim
rating
06/09/2025
Great seeds

Plants are in week two veg nearly and there coming on absolute monster only grown under 300w dual spec cfl and 125w cfl but again very strong Aroma and seeds cracked and popped within a day or so all 5

fandango
rating
16/08/2025
Cheerful, cheap, and of good quality.

I bought these because of the price (the cheapest seeds from Seed Stocker) and was satisfied with the result. They can be harvested indoors after just 9 weeks if they get a good start. Otherwise, it’s better to plan for a harvest after 10–11 weeks. Strong Critical-like smoke, but I don’t know how they perform outdoors.

Steffen
rating
09/08/2025
T.N.T. in a jar

An absolute blast to the head. The first smoke hit like a bomb. Intense, makes you happy and quickly turns into a feeling of physical well-being. Great for pain (osteoarthritis). Reduces inflammation. Good yield in the greenhouse. Definitely growing it again. Lovely terps, had vanilla and a nice creaminess. Light citrus notes, especially grapefruit

Mr nice
rating
13/04/2025
Unbelievable

Outstanding! You will never see a auto grow like this one. Hats of to seed stockers!

Sloany Doany
rating
27/03/2025
Love it!

Great Strain! Grow it every year!

rev
rating
16/11/2024
strong enough!

It’s a strong smoke, and that’s really all you need to know. She did well under my 400W HPS. I’ve grown her in soil and in coco, and with coco I got just a bit more yield. Very easy to grow and fast – ready in 73 days. But the reason to grow her is the quality of the Critical smoke.

pilot7
rating
16/11/2024
Easy to grow!

It was the easiest and least demanding of the 5 autoflowering strains I grew in September 2017. The others were various freebie seeds from Attitude. It reached 70 cm tall and I got about 65 g from it – sticky, sweet and potent. I'll definitely grow it again, I was really impressed for cheap autoflowering seeds.

Fron
rating
15/08/2024
Easy and reliable

Great variety for my greenhouse, the plants require little care and produce a good yield. I love it! It’s a very commercial variety!

M.W
rating
02/06/2024
a beautiful plant ;)

a beautiful plant ;)

F.N.
rating
25/11/2023
BCN XXL

This is outstanding POTENT Marijuana. The Smell is out of this world. I never expected it to be as good as it was that is a fact. And large the plant gets huge.

ZanderBlander
rating
22/07/2023
WTF Genetics!

Wow, genuinely without a doubt the strongest autoflower I've ever had! First I grew it outdoors in the summer and then indoors in my little grow room too. Big buds and yields every single time. Definitely worth it, I sell most of it to the shop and they're happy every time too. wish I had more grow rooms!

Teskio90
rating
18/03/2023
Bcn critical auto

Absolutely fantastic, tried them for the first time and I'll definitely get them again

Mr kush
rating
19/06/2021
Top

Impeccable service. Good quality seed. I'll keep you posted

Anpon
rating
14/05/2021
Truly XXL size

3 seeds and they all germinated. I'm a beginner and I'd never seen such a big seed. It's in week six and it's definitely the tallest plant I've grown. The harvest will surely be just as big

Lauris
rating
10/12/2020
Arrived fine, germinated well

Arrived fine, germinated well

Diablo79
rating
18/11/2020
Awsome

I've had a few from seedstockers now and I love the xxl critical and am now getting good results from blackberry gum autos so definitely a good firm, well done guys

Adrien3182
rating
20/09/2020
Very beautiful plants

10 out of 10 germinated, very beautiful, sturdy, productive plants. I've got one dwarf that grew 4 main tops, 4 that are turning purple and 5 just like the photo, with big buds, one main branch and 4 branches growing upwards. Very nice smell, pretty strong at times.

Haddock44
rating
17/09/2020
Review

Honestly, what more can I say, great yield, fruity taste, packs a serious punch. Everyone loves it

RustyStarbuck
rating
17/09/2020
Bcn Critical xxl first grow

This is my first grow and I am so glad I chose the Bcn critical xxl.. I have 3 in week 6, 1 well into preflower and the other 2 are just turning now with pistils showing. I have another one in the seedling stage.. They take whatever novice mistakes I make, they love a feed and bounce back from everything so far and just keep going.. They respond well to lst and 20 hours light.. Can't wait for them to finish.

Thomas
rating
26/07/2020
5/5

Arrived quickly and in good order, all 5 seeds germinated perfectly. Today they're moving into their home. See you in two months!

monk
rating
03/06/2020
3/3 germinated - super hardy

all 3 germinated but unfortunately my cat destroyed them all. or so i thought. i chucked them into a waste pile of mud and a few weeks later 1 has started growing. i moved it to a seperate pile of mud that i wasnt adding to and its still going, weather or not it floweres is another matter but gotta say she has really pulled through a lot of stress. they other 2 died- stupid cat. would recomend to a begginner if looking for a really easy and hardy plant.

That7dsgye
rating
17/05/2020
Great Smoke.... Will Buy Again

Plant needs about 11-12 weeks to finish. Check Trichomes before harvesting to ensure theyre milky/amber. You can gain about 4oz per plant with the right lighting. I used 900 watt LED and harvested 4oz per plant. She loves to drink so watch out for a proper watering and feeding scheduling. I grew my ladies in 3 Gallon smart pots. The buds are pretty easy to manicure so you can get them hung and dried. It took around a week to dry and now Im currently in curing stage and after about three day in the mason jars you start to smell the lemon scent terps. The smoke is so lovely... Its like a lemon lift and then youre relaxed and chill

DAZZY
rating
11/10/2019
CRITICAL XXL AUTO

Had 3 pips. 2 germinated 1 didn't. So the 2 that have germinated are now at day 43 and the phenotypes are completely different. Number 2 started flowering after only 21 days and is now well on it's way and standing at 60cm whereas number 1 is only now showing signs of flowering. She stands at 53cm and is much stockier and bushy. As it happens I am quite happy with this result as I will be able to finish bot a different times. Overall I would say that for my first go at autos I tried a good strain. It is a little finicky for the first 14 days but when she has settled in to her rhythm she goes wild and you can almost whatch her grow. Definitely one for the novice to have a go at growing. From what I have read up compared to some other auto plants this strain is pretty forgiving and responds well to some minor mess ups.looking at number 2 and the bud sites that she has already produced I think she will do exactly what it says on the tin and get to that XXL crop that is promised. Go on give her a go and I pretty much guarantee a bumper harvest.

MichaelBEAR
rating
22/09/2019
ONE OF THE BEST WEED OUT THERE. THE AROMA IS AMAZI

ONE OF THE BEST WEED OUT THERE. THE AROMA IS AMAZING

maradona
rating
21/09/2019
The best seeds so far! I enjoy the fee

The best seeds so far! I enjoy the feeling and the plants were spectacular

arseniii
rating
21/09/2019
tasty tasty tasty, you really start thinking

tasty tasty tasty, you really start thinking in a new way=) mine were shorties, 0.7-0.9 m tall, smelled like a whole field of flowers

Happy Camper88
rating
01/08/2019
Top Notch

These are just top notch!

Juazzzer
rating
12/07/2019
Easy to grow

Wow! this grow was the first time ever the plant reacted well to all circumstances. I also got more experience but at least in my set up this is a very easy to grow critical seed. It are also cheap cannabis seeds so I will definitly grow this one more times. High yield, strong smoke, perfect for big indoor grows!

BGrower67
rating
11/07/2019
I like big buds

And i cannot lie! Wow these buds are amazingly big XXL

Jean-Paul
rating
01/07/2019
WTF...

Hi all! Thank's the team. Really. All plants from your automix are happily messing around in my green house! 2 months from germinating, more or less, and NL auto is 2 meters high, full of flowers, BCN critical auto and amnesia auto are just 20 centimeters less, OSR auto almost as tall. Full power, vigourous growth and blooming is already full of promises... A real jungle where it is hard to see other plants like tomatoes and chilis... Once again, THANKS!

Canabis
rating
16/04/2019
Great site

Fast, discreet delivery and a little gift thrown in too. 5/5 germinated, I'm waiting for the rest and I'll keep you posted

D.M
rating
27/03/2019
No complaints

Easy to grow, great smoke, great price and great xxl yields, I grew 1 along with a couple of different strains on my first grow and the bcn critical xxl outgrew the rest, give it a go, you won't be disappointed

D.M
rating
18/03/2019
Wowsers

Easy to grow, a great strong smoke and a great price, and they are not joking about the xxl, grew 1 along with a couple of other different strains on my first grow and she yielded almost 3 times more than the others, just over 4oz, that was with a 250w hps dual spectrum, so absolutely no complaints, thankyou Seedstockers

Bud
rating
19/02/2019
Kiváló

Alle Samen sind schön gekeimt. Sie wachsen gut. Hervorragendes Preis-Leistungs-Verhältnis. Danke. Ich werde wieder bestellen.

Otto
rating
21/12/2018
BCN Critical xxl autoflower

Such a great plant. It will give you perfect plants in every condition. Fat buds, nice smell, big harvest and lovely smoke.