Sexing

Sexing cannabis is the process of determining a plant's biological sex, a critical task for growers using regular (non-feminized) seed because males produce no smokable flower and will pollinate any nearby females, ruining the crop with seeded buds. Sexing is performed by inspecting pre-flowers at the internodes during late vegetative growth (week 4-6) using a 10x loupe, jeweler's magnifier, or smartphone macro lens. Female plants display teardrop-shaped calyxes with two white V-shaped pistils emerging from the tip; male plants display round pollen sacs on short stalks resembling tiny grapes or balls. Sexing techniques: (1) Standard pre-flower inspection, examine internodes during late veg, looking for the diagnostic structures; (2) 12/12 from seed, flipping to flowering immediately forces sex expression within 7-14 days; (3) Cloning + flipping, take a clone from each numbered seedling, flip the clones to 12/12 to identify sex while keeping the mother plant in veg, then keep only the females; (4) DNA testing, labs like Phylos and Medicinal Genomics offer leaf-tissue sex tests with results in 2-3 weeks. With feminized seeds, sexing is only required as a hermaphrodite check, since 99%+ of plants will be female. Outdoor growers in legal regions face additional risk: airborne pollen from neighboring male plants can travel miles, fertilizing entire fields of females within hours. This is why feminized seeds dominate the modern market, they eliminate the entire sexing workflow and the risk of accidental pollination.