Chronic Strain

Chronic is a trade mark name invented and registered by us for the seeds we sell under this name since 1995.
F1-hybrid, Sativa/Indica hybrid

7 Awards total

Award no.1 Award no.1 Award no.2 Award no.2 Award no.3 Award no.3 Award no.3

The Chronic strain is our most commercial variety, this medium height, not too dense plant is the perfect combination of very good yield (up to 600 g/m2) and excellent quality. Smokers who appreciate high-quality and grow for themselves choose Chronic weed for its combination of appearance and sweet smell.Read more

Chronic Strain Characteristics
Recommended veg. time
Indoor flowering time
9 - 10 weeks
Indoor yield
350 - 800 gr/m2
Outdoor harvest time
mid/late October
THC levels
CBD levels
70,00 €

Chronic Strain Description

The Chronic strain is our most commercial variety, this medium height, not too dense plant is the perfect combination of very good yield and excellent quality. Smokers who appreciate high-quality and grow for themselves choose this plant for its combination of appearance and sweet smell. With its Indica genetic background Chronic weed production can be up to 600g/m2 without losing that special connoisseur feeling.


Grows a single huge central bud with few side branches. Topping of the plants to encourage the devlopment of multiple big side buds is possible, but the total yield can be a little less this way. A sweet smell develops while flowering and this aroma will be maintained in the finished Chronic weed, if it is dried and cured well before packaging. Putting the Chronic weed in plastic bags before it is thoroughly dry will destroy the subtle fragrance forever, making it a mediocre chronic weed. Out of all our strains, the Chronic strain is the best choice for growers who are tired of losing quality while increasing yield.

Already a winner of the 3rd prize at the High Times Cannabis Cup in 1994, this variety was improved in 2000. 1st prize at La Bella Flor Cup Spain 2003 (by Ezequiel) and 1st prize at Highlife Cup Spain 2004 (by Mundo Ganja, Alicante). 2nd prize Highlife Cup Spain 2004, category: Hydroponic (by Perenne Grow, Barcelona). Last awards won by Chronic: 3rd prize Copa Green Skull 2016, category: Solventless Extracts, Cabezon de la Sal, Spain and 3rd prize Cata Invernal 2016, category: Drysief, Spain.

Chronic - Maybe the fattest bud on earth

Text & Photos: Green Born Identity – G.B.I.

Every cannabis seed breeder strives to create the optimum combination of quality, quantity and potency. A variety that produces heavyweight flower tops with a delicious smell and tasty aroma that virtually drip THC from vast amounts of resin glands. Well, Serious Seeds for example certainly is a seed bank that has managed to achieve this goal, having bred the famous Chronic strain. With its introduction in 1994, it set a new standard in terms of combining superior yield, flavour and potency excellence in one plant. If growing and harvesting would be an active part of the High Times Cannabis Cup`s testing ceremony, the Chronic strain surely would have gained more than just 3rd place in the hydro category in 1994, when it had been entered in the Cup for the first and only time. Because every grower who properly cultivates this strain stands mouth wide open in front of his plants at harvest time, stunned by the Chronic`s enormous cola size and flower beauty. The buds not only are huge, but also nearly leafless, nicely composed of abundant small single flower clusters that add up to large colas with the size of a brick or even bigger.

The pedigree of chronic is very classic, consisting of Northern Lights / Skunk x Northern Lights / AK-47 strain. This is the formula of today`s Chronic strain. The original one, being in existence during the 90`s, had no AK in it. But by the late 90`s, Simon, the breeder of Serious Seeds, thought that his Chronic was kind of “dated”, as he puts it, and had to be refreshed and made more complex by breeding in a slight degree of superior new genetics. He decided for his proven AK-47. It was of utmost importance not to lose any of those marvellous characteristics that had made the strain so popular amongst worldwide growers. Simon reports: “I bred more sativa into the indica dominant Chronic, which gave it a more complex, full-spectrum high without losing the nice yield and flavor. The facelift also improved both the strength and resin content. The mildly sweet scent with a bit of spiciness also stayed intact.” The grower has to keep a special eye on the drying process in order to preserve this honey-sweet aroma. Simon gives the following recommendations: “Even while living, the wildflower scent is subtle, but it will be lost for good if not dried properly. When put in plastic before completely dry, the scent is irreversibly gone, more so for this variety than for any others I've worked with. But if you let it dry thoroughly, the aroma develops a very strong, sweet smell which doesn't fade. For flavor connoisseurs, this could be the difference between thinking Chronic weed is fabulous or just okay.”

So at the beginning of the new millennium, the Chronic strain was reborn and nowadays is stronger than ever, a fact that I recently could convince myself of, having the opportunity to see and shoot splendid specimens of the Chronic weed, grown by “Mr. Power-Planter”. He had sowed five original Chronic seeds, three of which turning out to be female. They were grown on soil in 15 litre pots, watered and fertilized by a drip-feeder system. 33 days after germination, Mr. Power Planter switched the timer to 12 hours light and 12 hours darkness, inducing the plants to enter the flowering stage. What happened very quickly, already within 5-7 days the plants showed their gender. One of the remaining three ladies was pruned for clone production at the main stem so that it grew into a set of strong side branches. While Simon recommends “not to top the plants to encourage multiple big buds, as this strain does not respond well”, this pruned Chronic plant turned out to be a real 102 cm-bomber in the end, exhibiting five tremendous rock-hard top colas and four very well-shaped tops in the lower region of the plant. So at least with this Chronic individual, Simon`s rule was disproved, but this plant probably was an exceptional specimen, with an outstanding hybrid vigour effect. Mr. Power Plant of course was very happy about having selected this especially powerful plant for clone production. The second plant had an impressive top cola and a couple of very well developed side branch colas, reaching 94 cm at harvest time. The third plant measured 80 cm and was not as spectacular as the other ones, but still an excellent indoor plant. Flowering time was 66 days for the “mighty bush”, 68 days for the second and 65 days for the third plant. All of the buds were extremely dense and could very easily be processed at harvest time, as the plants exhibited a high calyx-to-leaf ratio. They were cured and dried very carefully, keeping in mind what Simon had said about the Chronic weed precious, but fragile wildflower scent. When the dry harvest was put on the scales, it was like Eastern and Christmas together for Mr. Power Planter. The multiple top cola bush yielded amazing 85 grams, the second one above-average 58 grams and the third one still respectable 47 grams. Also the aroma, taste and high of the buds fulfilled any expectations, these chunky nuggets were a sweet pleasure to smoke and delivered a long-lasting high that expressed both the sativa and indica spectrum. No wonder that Mr. Power Planter has already started growing the first batch of clones… his new discovery Chronic will keep his garden occupied for a long time, as he said - with a broad smile in his face.

According to Simon, the Chronic strain can also be successfully cultivated under natural light, but has to be grown in a protected environment, e.g. on a sheltered balcony or under glass resp. foil. Ripening time is 15-31 October.


Green Born Identity – G.B.I.

All enquiries please contact Serious Seeds
UK Official Distributor

Tele No: 020 8964 1717
It is illegal to germinate seeds in the UK


Cultivation data:

Strain Chronic (3 female plants grown from seed)
Pedigree Northern Lights/Skunk x Northern Lights/AK-47
Genetic type Sativa/Indica
Vegetative stage 33 days (after germination)
Flowering here 66, 68 and 65 days, in general 60-67 days
Medium standard grow-mix
pH 6.2-6.8
EC up to 2.0 (nutrient solution)
Light 1000 + 600 W HPS
Temperature night: 18 °C day: 24-28 °C
Air humidity 40-75 %
Watering drip-feeder system
Fertilizer (veg. stage) Canna Terra Vega
Fertilizer (flowering stage) Canna Terra Flores
Stimulators “Exelent Explosief” bloom stimulator
Height 102/94/80 cm
Yield here 85/58/47 grams, in general up to 600 grams/m2

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