Cannabis is classified into chemotypes based on the ratio of THC to CBD in the flower. The ratio is genetic — it's set the moment the seed is made, and you can't change it later.

The three chemotypes
Type I (THC-dominant)
  • THC > 0.3% and high; CBD < 0.5%
  • What most modern commercial flower is
  • Genotype: BT/BT
Type II (balanced) & Type III (CBD)
  • II: THC and CBD roughly 1:1 — BT/BD
  • III: CBD-dominant, THC < 0.3% — BD/BD
  • Hemp falls in Type III by legal definition

Why this matters

  • If you want CBD genetics, you need both parents BD/BD. A single BT/BD parent will produce mixed offspring.
  • Type II plants are valuable for medical work. The ratio breeds true if both parents are BT/BD.
  • Marketing claims like "high CBD strain" mean nothing without a lab test confirming the chemotype.