From my perspective, the most common reason my leaves are detaching is that my roots are suffocating. You are being too kind with the water. My succulent body is designed to store vast amounts of water within my thick, fleshy leaves. When you water me too frequently, the soil stays constantly wet. My roots, which need oxygen as much as they need water, begin to rot in this soggy environment. Once the root system is compromised, it can no longer transport water and nutrients to the rest of my structure. In a desperate act of self-preservation, I will sacrifice my oldest, lowest leaves. They become soft, mushy, and translucent (often yellow or brown) before falling off at the slightest touch. This is not a gentle drop; it is a symptom of a critical system failure.
Conversely, you may be neglecting me for too long. While I am drought-tolerant, I am not immortal. When my internal water reservoirs are completely depleted, I must enter a survival state. To conserve the precious little moisture I have left for my core stem and newest growth, I will actively reabsorb the water and nutrients from my older leaves. This process is more controlled than in an overwatering scenario. The leaves will typically become wrinkled, flat, and may feel crispy or thin before they dry out completely and fall off. They often turn a lighter color or brown from the tip inward. This leaf loss is a clear signal that I have used up all my emergency reserves and require hydration to continue sustaining myself.
If my environment is too dim, I am programmed to seek out sunlight. This process is called etiolation. I will direct my energy into rapidly growing my stem, stretching out awkwardly and becoming leggy in a attempt to find a brighter light source. This rapid growth spurt is energetically expensive. To fuel this desperate reach for the sun, I will often reabsorb nutrients from my lower, older leaves that are no longer as efficient or are shaded by my new growth. These leaves will typically yellow, dry out, and drop off in a orderly fashion from the bottom up. While this is a natural form of self-pruning to some extent, excessive leaf drop coupled with a pale, stretched stem is a direct result of insufficient light.
Sometimes, the cause is an external invasion. Pests like mealybugs, scale, or spider mites see my juicy leaves as a perfect source of sustenance. They attach themselves to my leaves and stems, piercing my skin to suck out my nutrient-rich sap. This feeding weakens the leaf structure at the attachment point and drains the vital fluids that keep it plump and healthy. An infected leaf will often yellow, weaken, and eventually detach. You might notice sticky residue (honeydew), fine webbing, or the tiny pests themselves before the leaf falls. I am losing leaves because I am being eaten alive.
Finally, I am a creature of habit and sudden changes in my environment can cause significant stress, leading to leaf drop. This could be a dramatic temperature swing, a cold draft from a nearby window, or the physical shock of being repotted. When repotted, my root system can be slightly damaged and needs time to reestablish itself. During this recovery, I may not be able to support all of my leaves and will shed a few to reduce demand. Similarly, a rapid move from a sheltered indoor space to a harsh, full-sun outdoor patio can scorch my leaves, causing them to burn, scar, and eventually drop as I struggle to adapt.
