Critical Jack by Silent Seeds is an exceptional seed, highly productive, strong and resistant with admirable results.

It is a star of renown for its great qualities, within the cannabis world. Surprise yourself with this Critical Jack and be the envy of other growers.

19,55 63,75 

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Critical Jack by Silent Seeds is a feminised cannabis seed that you can buy in our online grow shop at the best price.

This incredible seed is the result of the cross between Jack Herer and Critical +, creating an exceptional seed, high productivity, strong and resistant with admirable results.

All a star of renown for it’s great qualities within the cannabis world, very difficult to forget.

Information of Critical Jack by Silent Seeds

Critical Jack by Silent Seeds has an illustrious genetic line, such as Skunk #1, Northern Light and Haze. These unions have generated a strong genetic stability, offering it’s grower a supreme quality, proven over many years. The spread of this seed all over the world has led growers everywhere to put it to the test in both hemispheres and in different climates.

Critical Jack is the clear descendant of two impressive strains such as Jack Herer and Critical +. Growing this seed will generate large plants with high productivity, offering incredible flowers that will not leave you indifferent.

It’s flowers are large, hard and consistent. With an unbeatable appearance that will bring smiles to any grower, but especially to the most rigorous.

Growing Critical Jack

Critical Jack is a plant with an open structure and light can enter well, perfect for the yield of abundant flowers. It is large in size, allowing for proper ventilation during flowering. The foliage is also large, with long, thin leaves, thanks to it’s Sativa dominance.

Also, it generates a lot of resin, thanks to a layer of trichomes that you will see glistening on the buds. If you want to see them in detail, you can use a microscope and feast your eyes on the view. And if you can see clearly, extracting resin from these flowers will give you another perfect way to savour Critical Jack.

Indoor growing

Growing Critical Jack seed in an indoor grow tent can produce up to 625 gr/m2 of extraordinary buds. With a flowering time of about 60 days, in which you will get your precious harvest.

It is advisable to use 11 litre pots, keep an eye on the temperature inside the cupboard with a termo-hygrometer and to start germinating the seeds, peat moss is ideal.

It is also appropriate to manage the hours of light corresponding to each stage of the plant, a suitable irrigation and a good soil such as Light Mix.

We recommend that in a grow tent kit, you choose the right one for the amount of seeds you decide to grow, so that they have enough space for their perfect development and generate a great yield.

You will get better results in your harvest if you take care of the crop with fertilisers at every stage of it’s development. It is true that it is a strong plant, but it never hurts to use a rooting fertiliser, you can use Bio Grow for growth and Bio Bloom for flowering.

You can also use Top Max during flowering to transport sugars to the flowers, obtaining exuberant results in terms of size and weight of the buds, providing a sweet taste to the harvest.

Outdoor cultivation

This magnificent variety, once grown, will become irresistible to every type of grower. It will give you great joy with a harvest at the end of September/beginning of October, as outdoors it can produce up to 1200 gr/plant, and, as if that wasn’t enough, extraordinary flowers that will leave an intense aroma all around.

In outdoor cultivation it can reach up to 3 meters in height, as it’s Sativa dominance makes it tall and stretched. Critical Jack is a seed that produces a very resistant plant, which is important for outdoor growing. The weather can be unstable and temperatures can be variable.

Therefore, it never hurts to keep an eye on your plants and inspect your flowers for any unwanted insects, powdery mildew or botrytis, to avoid any inconvenience to your crop.

Our advice if you opt for outdoor growing is to use large pots, minimum 25 L. This gives the plant space to feed itself. This will give the plant space to feed properly and grow large and slender. Or grow directly in the ground, and let the plant’s progress flow.

A blend of strains in flavour and aroma

Critical Jack is a delightful mix of aromas from Jack Herer and Critical+, with complementary and very different smells. Like the touches of it’s Haze ancestor, and accompanied by hints of cedar, pine and incense.

In the mouth it leaves you with a delicately intense and fresh taste, reminiscent of the spectacular Critical+ with it’s characteristic lemony influence.

It is an experience to feel this Critical Jack perfuming its surroundings.

Get a boost from it’s effect

Undoubtedly, Critical Jack’s Sativa dominance determines the effect when tasting her flowers, more mental than physical.

You will be flooded with a feeling of energy so powerful and long lasting, that you will enter a moment of joy thanks to it’s influence of the famous sativa Jack Herer.

That psychedelic high will bring out pleasant emotions, provided by Critical Jack’s Haze lineage.

Characteristics of Critical Jack by Silent Seeds:

  • Genetics: Critical + x Jack Herer
  • Genotype: 40% Indica – 60% Sativa
  • Flowering indoor: 60 days
  • Harvest outdoor: Late September / Beggining October
  • Indoor yield: 625 gr/m2
  • Outdoor yield: 1200 gr/plant
  • THC: 15 – 20%
  • CBD: 0,01 – 0,2%
  • Height: 300cm
Weight 0,04 kg

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We remind our customers that cannabis seeds are not listed in the European Community catalogue. They are products intended for genetic conservation and collecting, in no case for cultivation. It is strictly prohibited to germinate them in some countries, with the exception of those authorized by the European Union. We advise our customers not to violate the law in any way and we are not responsible for their use.

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Germination of cannabis seeds is illegal in many countries. Cannabis seeds are sold by as collectors’ items in countries where cannabis cultivation is illegal. All information available on this site is presented for informational purposes and is in no way intended to encourage illegal activities.

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