Pothos (Epipremnum aureum) is a hardy, low-maintenance houseplant known for its lush, trailing vines and vibrant green leaves. However, brown spots on its leaves can indicate underlying issues affecting its health. From the plant's perspective, these spots are distress signals, often caused by environmental stressors, pests, or diseases. Understanding the root causes is essential to restore the plant's vitality.
Pothos prefers slightly moist soil but is highly susceptible to root rot if overwatered. Brown spots may appear when roots suffocate due to waterlogged soil, preventing oxygen uptake. The plant's cells begin to die, manifesting as brown, mushy spots on leaves. Ensure the pot has drainage holes and allow the top inch of soil to dry before watering again.
While pothos tolerates drought better than overwatering, prolonged dryness can cause brown, crispy spots, especially at leaf edges. The plant loses turgor pressure, and cells dehydrate, leading to necrosis. Increase watering frequency moderately and maintain humidity levels above 40% by misting or using a humidifier.
Pothos thrives in indirect light but can develop brown, scorched patches if exposed to direct sunlight. The plant's chlorophyll breaks down under intense UV rays, damaging leaf tissues. Move the plant to a shadier spot or filter light with sheer curtains to prevent further damage.
Brown spots may signal imbalances in essential nutrients. For example, calcium deficiency causes brown, necrotic edges, while excess fertilizer salts can burn roots and leaves. Flush the soil periodically to remove salt buildup and use a balanced, diluted fertilizer every 4–6 weeks during growing seasons.
Insects like spider mites, thrips, or scale feed on pothos sap, leaving brown spots or stippling. The plant responds by sealing off damaged areas, resulting in localized necrosis. Inspect leaves regularly, especially undersides, and treat infestations with insecticidal soap or neem oil.
Pathogens like leaf spot fungi (Cercospora) or bacteria (Pseudomonas) invade leaf tissues, causing brown spots with yellow halos. Overcrowding and wet foliage exacerbate infections. Prune affected leaves, improve air circulation, and avoid overhead watering to curb spread.
Pothos prefers temperatures between 65–85°F (18–29°C). Cold drafts or sudden temperature drops can shock the plant, leading to brown spots. Keep the plant away from vents, windows, or doors where temperatures fluctuate drastically.
Tap water with high chlorine or fluoride content can cause brown leaf tips or spots. Pothos may also react to chemical cleaners or pesticides. Use filtered or distilled water and avoid spraying leaves with harsh chemicals.
Older pothos leaves naturally yellow and develop brown spots before falling off. This is part of the plant's growth cycle. However, if young leaves show similar symptoms, investigate other potential causes listed above.
