Yellow leaves on a Monstera deliciosa are one of the most searched plant problems online. The frustrating part is that yellowing has multiple possible causes — and the fixes for some of them are the opposite of others. Watering more fixes underwatering; watering more makes overwatering worse.
Here are the 7 causes ranked by how often they're actually responsible, so you can work through them in the right order.
1. Overwatering (most common by a large margin)
Symptoms: Leaves turn yellow across the whole plant, not just lower or older leaves. Soil stays wet for 10+ days. Leaves may feel soft or slightly mushy near the base.
Why it happens: Monstera roots need oxygen. Constantly wet soil suffocates them, preventing nutrient uptake even if nutrients are present. The plant essentially can't feed itself.
Fix: Stop watering immediately. Let the soil dry out until the top 5–7 cm is fully dry, then water thoroughly. If the pot lacks drainage holes, repot immediately — drainage holes are non-negotiable. If you suspect root rot (mushy, dark roots), pull the plant out, cut off rotten roots, dust with cinnamon (a natural antifungal), and repot in fresh well-draining mix.
Prevention: Water only when a finger 5 cm into the soil comes out dry. In winter, this might be every 2–3 weeks.
2. Natural leaf aging (entirely normal, stop worrying)
Symptoms: One or two lower leaves turn yellow at a time, starting at the tip and progressing toward the petiole. The rest of the plant looks healthy.
Why it happens: Monsteras regularly shed their oldest, lowest leaves as they grow. This is normal housekeeping. The plant is redirecting energy to new growth.
Fix: None needed. Remove the yellow leaf cleanly at the petiole to prevent rot spreading. If you're losing more than 2–3 leaves per month, combine this with the other causes below.
3. Inconsistent watering (drying out too much between waterings)
Symptoms: Yellow patches on leaves, dry and slightly crispy at the edges. Soil has pulled away from the pot edges. Lower leaves yellow first.
Why it happens: When Monstera dries out severely and repeatedly, roots die back. Subsequent waterings can't be absorbed efficiently, causing patchy, irregular yellowing.
Fix: Establish a consistent watering rhythm. Check the soil every 5–7 days and water when the top 5 cm is dry — don't wait until the soil is bone dry throughout.
4. Too little light
Symptoms: Gradual, pale yellowing of leaves (not patchy or spotted). New leaves are smaller and without fenestrations. Plant is stretching toward the light source.
Why it happens: Monsteras produce chlorophyll using light. In insufficient light, the plant can't maintain the chlorophyll in existing leaves, which gradually turn yellow.
Fix: Move to a brighter spot with bright indirect light. A north-facing window is usually too dark; south or east-facing is better. If relocation isn't possible, a 10W full-spectrum grow light on a 12-hour timer makes a significant difference.
5. Root-bound in too small a pot
Symptoms: Yellow leaves on a plant that's been in the same pot for 2+ years, with roots growing out of drainage holes or visible above the soil surface.
Why it happens: When a pot becomes too small, roots run out of room and the soil dries out too quickly between waterings. The plant starts cannibalising older leaves to sustain new growth.
Fix: Repot in spring into a container 5–7 cm wider. Use a well-draining chunky mix — standard potting soil compacted in a larger pot is worse than being slightly root-bound.
6. Nutrient deficiency (usually nitrogen or magnesium)
Symptoms: Yellowing between the leaf veins (the veins stay green). Often starts on older leaves. Happens in plants that haven't been repotted or fertilised in over a year.
Why it happens: Old potting mix loses nutrients over time, especially if the plant has been in the same soil for 2+ years with no feeding.
Fix: Fertilise with a balanced liquid feed (NPK 10-10-10 or 20-20-20) at half-strength once per month during spring and summer. If the yellowing is specifically between veins, a magnesium supplement (Epsom salt dissolved in water, 5ml per litre) can correct it within a few weeks.
7. Pests: spider mites or thrips
Symptoms: Yellow spots or stippling on leaves (not uniform yellowing). Tiny moving dots visible on the underside of leaves (spider mites) or dark specks and sticky residue (thrips).
Why it happens: Both pests feed on leaf cells, causing the cells to die and turn yellow. They're often introduced via new plants or by an open window.
Fix: Quarantine the plant immediately. For spider mites, spray the entire plant (including leaf undersides) with water, then apply neem oil spray or insecticidal soap every 5–7 days for 3 weeks. For thrips, use a systemic insecticide (spinosad or pyrethrin) and sticky traps. Check every other plant nearby.
Quick diagnostic checklist
When you see yellow leaves, answer these in order:
- Is the soil wet or waterlogged? → Overwatering (fix immediately)
- Is it only 1–2 lower leaves? → Natural ageing (normal)
- Has the soil been very dry? → Inconsistent watering
- Is the plant far from a window? → Low light
- Has it been in the same pot for 2+ years? → Root-bound
- Has it ever been fertilised? → Nutrient deficiency
- Any dots or specks on leaves? → Pests
Work through this list before changing anything. The most common mistake is assuming yellow leaves mean the plant is thirsty and watering more — when overwatering is already the cause.
PlantWatch's AI health check can help: upload a photo of the yellow leaves and get a diagnosis with treatment steps specific to what it sees. Useful when the visual clues aren't obvious.