Feminized seeds are made by forcing a female plant to produce pollen, which is then dusted onto another female. The resulting seeds are nearly 100% female because both parents only carry X chromosomes.

Three methods, three outcomes
STS (silver thiosulfate)
  • Most reliable — the modern standard
  • Sprayed early in flower
  • Used by virtually every commercial breeder
CS (colloidal silver) & Rodelization
  • CS: hobbyist-friendly, less consistent
  • Rodelization: let a stressed female self-pollinate — least reliable
  • Rodelization is sometimes marketed as "natural" — fine, but unstable
Do feminized seeds herm more?+
Poorly made ones do. Quality STS-made seeds from selected mothers don't.
Why are feminized seeds more expensive?+
Each pack requires a flowered mother, a reversal cycle, and longer test grows. The labor adds up.