Sour Diesel, sometimes abbreviated as Sour D, is an extremely popular strain, distinguished by the fuel-like chemical smell of its flowers. It has a mostly sativa head high with some subtle physical indica relaxation, making it popular among recreational and medical users alike. This is a potent strain, with a THC content that had been measured at between 20% and 25%.
Because the underground cannabis market of the 1980s and 90s operated without any kind of lasting documentation, the exact origins of Sour Diesel are not known. Although a definitive agreement on its original genetic makeup doesn't exist, Sour Diesel’s popularity has made it the subject of much speculation. Some believe that true Sour Diesel was derived as a distinct phenotype of an original strain simply named Diesel. Others say that it was a phenotype of Chemdawg that leaned more sativa than indica. Still others claim that it was a cross of Chemdawg and Northern Lights, or perhaps Chemdawg, Northern Lights, and Skunk #1.
Sour Diesel has round, medium-sized buds with leaves that appear yellowish-green. Red hairs called pistils, structures that operate to catch pollen from male plants, contrast with the densely-packed leaves. When properly cured, the flowers are somewhat sticky -- the dusting of trichomes is not as immediately obvious as it is on more resinous strains like White Widow. Nevertheless, breaking open buds reveals trichomes coating the insides of the dense flowers. The buds have an overpowering smell that, true to this strain’s name, is very similar to gasoline. The odor also has some hints of orange. Breaking open or grinding the buds intensifies this scent, and adds components of musk and pine sap. Sour Diesel has a notoriously harsh, acrid smoke that can cause users to cough or make their sinuses water. The smoke has a sour and vaguely skunky taste that many describe as unpleasant; on the exhale, the diesel's almost ammonia-like tang stings the palate and may linger for a long time afterward. Smokers trying to remain discreet should be warned that this is a very pungent strain whose odor can carry for quite a distance.
The high from Sour Diesel comes on users quickly in the form of a warm and pleasant head rush. An uplift in mood may be noticeable as well. Although Sour Diesel stimulates synaptic activity in the brain, the character of this head high is more spacey than intensely cerebral. Users may feel chatty if surrounded by others or somewhat introspective if enjoying the strain alone. For many, this soaring high is partially anchored by a slight feeling of physical relaxation. That said, a body stone that leads to full-on couchlock is rare. The sense of euphoria that comes with this variety may be helpful in treating some symptoms of mild stress, anxiety, or depression. Its tendency to lead to associative thinking may provoke a bit of creative inspiration. Fans of the strain also describe relief from troublesome aches and pains. Sour Diesel’s combination of mental and somatic effects may also make it a potent aphrodisiac in certain situations. As is common with many strong sativas, the altered mental state brought about by Sour Diesel may prove overwhelming for some, leading to paranoid, recursive thinking or a feeling of being generally “out of control” of one’s thoughts or body. Users, especially those with a lower THC tolerance, should adjust their intake accordingly. Sour Diesel has an average-length high that lasts about 2 to 3 hours.
Seeds of Sour Diesel are packaged and available for sale from several seed bank retailers. Growers can also raise plants as clones, taking clippings taken from fully grown plants of the same strain. Sour Diesel can be grown indoors or outdoors, although outdoor cultivation requires semi-humid, Mediterranean-like climates with daytime temperatures between 72 and 80 degrees Fahrenheit. The plants are more characteristically sativa than indica, with a tall, spindly appearance and large spaces between flowering nodes. Plants can grow to be over four feet tall, with their height increasing exponentially during the flowering stage. For those growing indoors, bending and pruning branches early in the vegetative stage may help train the plants to fit within limited vertical space. Sour Diesel flowers within 10 weeks when grown indoors and around early November when grown outdoors. It has a moderately high yield: growers can expect between 42 and 56 grams (or between 1.5 and 2 ounces) per square foot of plant."
Quoted from https://www.wikileaf.com/strain/sour-diesel/