Ultra Sour has a tart lemon-diesel flavour and its aroma is a combination of pine and diesel. It has a potent THC level. Ultra Sour is an indica-dominant hybrid strain that was created by THSeeds, which is one of Amsterdams most innovative cannabis seedbanks. The strains lineage is attributed to a cross between the MK Ultra and East Coast Sour Diesel strains. Its buds are deep green with bright rusty orange fiery orange hairs and a coating of dusty amber colored crystal trichomes.