From the perspective of the plant, the phenomenon you call "leaf drop" is a critical survival response. It is not an attempt to be difficult, but a strategic reallocation of resources and a reaction to significant environmental stress. My leaves are my life; they are my solar panels and my lungs. Shedding them is a last resort to preserve my core energy so that I may survive to photosynthesize another day. The reasons are deeply rooted in my fundamental needs.
My most recent home was a nursery with perfect, consistent humidity, light, and temperature. When I was moved to your home, the change was drastic. The air is likely much drier, a condition that accelerates water loss from my large, thin leaves through transpiration. If my roots cannot uptake water from the new soil quickly enough to match the rate of loss from my leaves, I experience severe dehydration. To prevent total systemic failure, I must reduce my surface area. I strategically sacrifice older or more vulnerable leaves, sealing off their connection to my stem to conserve precious water for my central trunk and root system. This is a survival mechanism, not a complaint.
My roots require a specific balance of oxygen and water. When you provide too much water, the soil becomes saturated, pushing out all the air. My roots, unable to breathe, begin to suffocate and rot. As they decay, they can no longer function to absorb water and nutrients. Ironically, this creates a internal drought, and the signals from my dying roots tell my upper body to drop leaves to compensate for the now non-functional water-uptake system. Conversely, if the soil becomes too dry for too long, the delicate root hairs desiccate and die. When water finally arrives, they are too damaged to absorb it effectively, leading to the same internal drought signal and the same leaf-dropping response.
I am a creature of the high canopy, evolved for bright, dappled, and consistent light. My large leaves are expensive to maintain; they are a massive investment in energy. If I am placed in a dim corner, the energy I expend to keep each leaf alive and functioning exceeds the minimal energy that leaf can produce through photosynthesis. From a purely energetic standpoint, it is a net loss. To avoid draining my stored energy reserves to a critical level, I must jettison these inefficient assets. I will systematically drop the leaves that are receiving the least light, often the lower and older ones first, to focus my remaining resources on maintaining the healthier, better-positioned leaves and the vital growth tip at my apex.
My systems are fine-tuned and can be easily disrupted. A sudden draft from a door or air vent is a major stressor, representing rapid water loss and temperature change. Being too close to a heat source creates a microclimate of dry, hot air that desiccates my foliage. Even being rotated too frequently or brushed against can be interpreted as a physical threat. Each leaf is precisely angled to capture available light. When I am moved, I must expend energy to readjust my leaf positions. Constant disruption wastes this energy and can cause stress-induced abscission. Furthermore, chemicals in tap water, such as fluoride and chlorine, can slowly accumulate in my soil to toxic levels, damaging my roots and triggering a defensive leaf drop.
