The Pothos (Epipremnum aureum) is a resilient and adaptable houseplant. Despite its hardy nature, the plant often signals distress through yellowing leaves, a condition known as chlorosis. This change indicates that an environmental or cultural factor is unbalanced. Diagnosing the exact cause requires careful observation of the yellowing pattern and the soil condition.
Moisture Imbalance: Overwatering vs. Underwatering
Watering issues are the most frequent cause of yellowing leaves in Pothos. Overwatering leads to oxygen deprivation, causing roots to suffocate and die, which often results in root rot. When roots fail, the plant sheds leaves to balance moisture intake, resulting in soft, mushy, and uniformly yellow foliage. This yellowing typically starts with older growth near the base and may include dark brown or black spots, and the soil will feel perpetually wet.
To determine moisture level, insert a finger one to two inches into the soil. If it feels wet, overwatering is likely. Overwatered leaves droop but remain limp and soft. Underwatering, which is less common for this drought-tolerant species, presents different cues. Leaves affected by insufficient moisture turn yellow but become dry and crispy, often starting at the tips and edges.
The entire plant may appear wilted, but the leaves will feel brittle, and the soil will be completely dry, often pulling away from the pot sides. During drought stress, the plant conserves energy by rapidly yellowing and shedding older leaves. Adjust the watering frequency only when the top two inches of soil are fully dry to remedy both issues.
Light and Temperature Stress
The external environment significantly influences the Pothos’s ability to maintain healthy foliage. Light exposure that is either too intense or too scarce can trigger yellowing as the plant adjusts photosynthesis. Too little light slows energy production, leading to a slow, pale yellowing across the entire plant as it struggles to maintain chlorophyll levels. This systemic fading shows the plant is conserving energy by reducing resources dedicated to unproductive leaves.
Conversely, too much direct sunlight can cause immediate damage to leaf tissue. This damage, often described as sunburn, manifests as sudden, bleached, or whitish-yellow patches. The damage is localized, appearing on leaves facing the light source, and prompts the plant to shed these sections to prevent further water loss.
Temperature fluctuations also stress the plant, which prefers a steady range between 60°F and 85°F. Sudden temperature drops or placement near cold drafts, AC vents, or heat sources can shock the Pothos. This stress leads to widespread yellowing and leaf drop as the plant attempts to stabilize its internal functions.
Nutrient Deficiencies and Natural Leaf Aging
Yellowing leaves can indicate internal chemical needs or the natural end of a leaf’s life cycle. Natural aging (senescence) is a normal process where the plant reclaims mobile nutrients from older foliage before shedding it. This process is gradual, affecting only one or two of the lowest, oldest leaves at a time, which turn uniformly yellow before dropping. This limited, slow yellowing is a sign of healthy growth and nutrient recycling.
When yellowing is systemic, it often points to a deficiency in a mobile macronutrient like Nitrogen, a structural component of chlorophyll. Nitrogen deficiency causes the plant to cannibalize the nutrient from older leaves. This results in yellowing that starts in the mature, lower foliage and progresses upwards, while new growth remains small and thin.
Another factor mimicking nutrient deficiency is the buildup of mineral salts from tap water or excessive fertilizer. This accumulation can burn the roots and interfere with the plant’s ability to absorb water and nutrients. Symptoms include yellowing and browning leaf edges, indicating a problem with soil chemistry.
Post-Diagnosis Action Plan: Saving the Plant
Once the cause of yellowing is diagnosed, immediate action is necessary to stabilize the Pothos. The first step is to remove all affected foliage, as yellowed leaves cannot revert to green. Pruning allows the plant to redirect energy away from non-functional tissue toward new, healthy growth.
If overwatering is confirmed, inspect the plant for root rot. Gently unpot the plant and examine the root ball; healthy roots are firm and white or light tan. Rotted roots are dark, mushy, and often emit a sulfurous smell. Trim away any dark, soft sections using sterilized tools to prevent the spread of fungal pathogens. Repot the plant into a clean pot with fresh, well-draining soil, and do not water for several days to allow the cut roots to heal.
If mineral salt buildup is suspected, the soil must be flushed to remove excess accumulation. Slowly pour a large volume of distilled or filtered water through the pot—about four times the container’s volume—allowing it to drain completely. This action washes away excess salts from the root zone, restoring the soil’s ability to facilitate nutrient uptake. Allow the soil to dry out completely before resuming a proper watering schedule.