Selfing

Selfing is a breeding technique where a single plant pollinates itself, producing seed offspring genetically identical (or nearly identical) to the parent. This occurs naturally in hermaphroditic cannabis plants or is deliberately induced by breeders using colloidal silver or other gibberellic acid treatments to reverse sex expression. Selfing is foundational to creating stable, homozygous seed lines and is particularly valuable for stabilizing desirable traits across generations. The resulting seeds—called selfed seed or S1 generation—allow breeders to rapidly fix phenotypes and establish breeding lines with predictable genetics. Selfing differs from backcrossing (crossing offspring back to a parent) and outcrossing (breeding unrelated plants), each serving distinct roles in cannabis breeding programs.

Breeders employ selfing to rapidly homogenize genetic material and create true-breeding lines from elite or rare phenotypes. S1 and subsequent selfed generations (S2, S3) are essential tools for stabilizing cannabinoid profiles, growth structure, and terpene expression before wider distribution or commercial release.