Open Structure Phenotype

Open structure phenotype describes cannabis plants with widely spaced internodes and an airy, spreading branch architecture. Rather than dense, compact growth, open-structure plants exhibit elongated stem segments between leaf nodes and lateral branches that develop at greater distances from one another. This phenotypic expression is frequently influenced by photoperiod sensitivity, individual genetic lineages, and environmental factors like light intensity and airflow. Open structure plants are often tagged as taller, more columnar in form, and potentially higher-yielding in horizontal canopy arrangements. Breeders working with sativa-dominant or equatorial lineages commonly observe this trait, as it relates to natural adaptations in high-light, humid growing environments.

Breeders select for or away from open structure based on cultivation method and space constraints. Open-structure phenotypes can support higher flower counts per plant in ideal conditions but may require additional support and present different canopy-management challenges compared to dense types.