Leaf Shape Phenotype

Leaf shape phenotype refers to the observable physical structure of cannabis leaves, including blade width, serration patterns, and overall morphology. This trait exists on a spectrum from narrow-leaflet to broad-leaflet expressions, influenced by both genetic background and environmental conditions during development. Breeders track leaf shape as a marker for ancestry, as Sativa-type genetics commonly exhibit narrower, more delicate leaflets, while Indica-type plants often display broader, denser foliage. Leaf morphology can also influence light penetration, airflow, and overall plant architecture—factors relevant to cultivation strategy selection. Documentation of leaf phenotype helps establish lineage authenticity and predict growth patterns across generations.

Breeders use leaf shape phenotype as a phenotypic anchor in pedigree work, helping confirm genetic heritage and predict structural behavior in hybrid offspring. Consistent leaf morphology across generations indicates genetic stability and aids in stabilizing new cultivars.