Fan leaves, also known as foliage leaves, are the large, typically broad leaves of the cannabis plant that grow from the main stem and branches. They are called fan leaves due to their fan-like shape, with multiple leaflets radiating from a central point.
Fan leaves play a crucial role in the overall growth and development of the cannabis plant. They serve various functions, including:
- Photosynthesis: Fan leaves are the primary sites for photosynthesis, the process by which plants convert light energy into chemical energy. Chlorophyll, a pigment found in the chloroplasts of fan leaves, captures light energy and enables the plant to produce sugars and other organic compounds necessary for growth and energy storage.
- Transpiration: Fan leaves play a role in transpiration, which is the process by which plants lose water vapor through tiny pores called stomata. Transpiration helps regulate the plant’s temperature, nutrient uptake, and overall water balance.
- Nutrient Storage: Fan leaves store essential nutrients that the plant requires for its growth and development. During vegetative growth, fan leaves accumulate and store nutrients that are subsequently transported to other parts of the plant as needed.
- Shade Casting: The large size and arrangement of fan leaves can provide shade to lower parts of the plant, helping to protect them from excessive sunlight and heat. This shade casting can prevent damage from intense light and aid in maintaining optimal growing conditions.
While fan leaves are essential to the cannabis plant’s vitality and overall health, they are not typically harvested or consumed for their cannabinoid content. The highest concentrations of cannabinoids, such as THC and CBD, are found in the resinous flowers, or buds, rather than the fan leaves. However, fan leaves may contain trace amounts of cannabinoids and other compounds, albeit in much lower concentrations compared to the flowers.
During the flowering stage, when the cannabis plant shifts its energy towards bud production, some growers choose to trim or remove certain fan leaves. This practice is known as defoliation or leaf pruning and aims to improve airflow, light penetration, and overall bud development. By selectively removing specific fan leaves, growers can redirect energy towards the formation of larger, more potent buds.