In botany the calyx is the outer whorl of a flower, made of its sepals. In female cannabis the true calyx (perianth) is reduced to a thin, translucent membrane hugging the ovary, hard to see without magnification. The plump, resin-covered green pod growers point at and call a "calyx" is in fact the perigonal bract that surrounds it.
In practice
The grower usage is everywhere and isn't going anywhere: "calyx-to-leaf ratio", "foxtailing calyxes", "stacked calyxes". Read it as "bract". A high ratio means buds built mostly of swollen bracts with little leaf, which trims fast and carries more resin per gram.
Being precise matters in breeding notes and plant descriptions. A GB-ID record or a test guideline should say "bract" for the structure that carries the resin. Botanical papers on cannabis flower development (e.g. Spitzer-Rimon et al. 2019) use the correct terms, which makes them easier to read once you know.
Don't confuse with
- Bract: the leafy sheath around the flower that growers usually mean.
- Pistil: the ovary, style and stigmas; the calyx surrounds the ovary.
- Sugar leaf: a small true leaf, not part of the flower.
