Two strains called Black Jack from different seed banks, one from from Nirvana Seeds in the Netherlands and the other from Sweet Seeds in Spain.
Nirvana Seeds Black Jack
The Nirvana Seeds version of Black Jack, spelled “Blackjack” by the original breeder, is a cross of Black Domina and Jock Horror. This cultivar of Blackjack tends to produce a euphoric, energetic, uplifting head high, while carrying a flavor of fresh pine tree and sweet citrus.
According to Nirvana Seeds, the strain has mostly sativa lineage, grows short and produces medium-sized yields of large, pungent, trichome-heavy buds during a 56-to-63-day flowering period. Best suited for indoor grows, Blackjack can reportedly yield between 400 to 500 grams per square meter using the Sea of Green (SoG) method.
Black Jack by Sweet Seeds
The Black Jack strain bred by Sweet Seeds is a cross of Black Domina and the iconic Jack Herer strain.
According to Sweet Seeds, the strain is a well-balanced hybrid that tends to produce powerful psychotropic effects.