Growers searching for a technique to put their plants in the best position to produce higher yields should consider cannabis defoliation. This delicate procedure is the strategic removal of leaves from the plant that can dramatically impact health and production for better or worse, depending on how and when it is done.
Read on to find out the principles behind defoliation, how to assess a plant for defoliation and the best way to defoliate.
Why defoliation works: increased light exposure and improved plant health
Growers increase the plant’s overall light exposure through defoliation. Bigger yields are produced as more bud sites receive more light penetration and the opportunity to develop into full flowers rather than small “popcorn” nugs found below the canopy. Plants react very positively to methods that increase the amount of light exposure, which will encourage the plant’s overall photochemical production, resulting in higher cannabinoid concentration, fuller trichomes, and “loud” terpene profiles.
By defoliating, the grower also increases aeration below the canopy. The risk of mould, mildew, pests, and pathogens is reduced by creating more space for airflow. Removing larger leaves also reduces overall humidity and redirects energy towards flowering.
Cultivators can develop a better eye for their plants’ health and characteristics by spending time defoliating their plants. This can lead to many positive outcomes, such as timely identification of pests, viruses, and diseases and identifying desired traits. The grower who removes extra leaves that do not directly support bud development will help their plants make more efficient use of limited resources and light.
Less is more: the role of leaves in plant growth and defoliated plants
Cannabis plants need their famous leaves for photosynthesis to occur as the crucial light-absorbing chemical chlorophyll is found most abundantly in leaves. As such, the challenge of defoliating is for the grower to remove fewer leaves than they think they will need because removing too many leaves will stunt the plant’s growth. Plants with a greater surface area of leaves to absorb light will grow more vigorously.
Conversely, bud sites found lower down the stalks of cannabis plants will not develop to the same level as their canopy counterparts due to being shaded by leaves. Growers who strategically defoliate will expose bud sites to direct light and airflow, which will increase their yield and bud density. At the same time, defoliation will cause the plant to redirect its resources away from superfluous leaves and trigger surges in plant growth.
Why should growers remove leaves? After all, they are a source of photosynthetic production and nutrient storage, which can be tremendously valuable, especially for plants outdoors that need to contend with environmental stressors such as pests and inconsistent nutrient availability during the growing season.
In a controlled grow room environment, these challenges are mitigated. If the grower is doing their job correctly, the plants will never want nutrients, the conditions are stable and monitored, and proper precautions are taken to minimise the risk of pest infestations. Thus, the need for leaves isn’t as pronounced indoors, and growers who defoliate strategically optimize light availability in the grow space and redirect energy towards developing bud sites.