Bract Formation

Bract formation refers to the development and structure of leaf-like structures that surround cannabis flower sites. These modified leaves are distinct from fan leaves and play a functional role in protecting developing floral tissues. Bract density, shape, and trichome coverage vary significantly across cultivars and are often influenced by both genetics and growing conditions. Breeders working in this category observe that bract phenotypes can affect visual appearance, calyx-to-leaf ratio, and overall flower architecture. Understanding bract morphology is relevant for cultivation assessment, breeding selection, and distinguishing between different genetic backgrounds.

Breeders selectively work with bract traits to develop cultivars with specific flower structures—some targeting dense, tight bracts for compact morphology, others selecting for more open architecture. Bract expression is a heritable characteristic useful for establishing and maintaining distinct phenotypic markers within breeding lines.