Short answer
Brown spots on Monstera deliciosa leaves are most commonly caused by root rot from overwatering or low humidity causing crispy edges. The most effective fix is to ensure the plant is in well-draining soil and allowed to dry out properly between waterings.
Brown spots on a Monstera often start as small, discolored lesions that may eventually turn crispy or develop a yellow halo. While some minor spotting is a normal aging process for older leaves, sudden or widespread browning is usually a signal that the plant's environmental conditions are unbalanced.
Excessive moisture prevents roots from accessing oxygen, leading to tissue decay that manifests as dark, mushy spots on leaves. This is the most common cause of sudden leaf decline in Monstera plants.
Check: Gently lift the plant from its pot and inspect the roots; healthy roots are firm and white, while rotting roots are mushy, dark, and may have a foul odor.
Fix: Immediately trim away all mushy root tissue with sterile shears, repot into fresh, chunky aroid soil mix, and ensure the container has functional drainage holes.
As a tropical epiphyte, Monstera deliciosa thrives in high humidity; when exposed to dry, arid indoor air, the edges and tips of leaves often brown and become brittle. This is a physiological response to transpiration occurring faster than the plant can absorb water.
Check: Check if the browning is primarily concentrated on the leaf tips and margins rather than isolated spots in the center of the leaf.
Fix: Group plants together to create a microclimate or place the Monstera near a humidifier to maintain humidity levels above 50%.
The accumulation of unabsorbed mineral salts from fertilizers can 'burn' root tips, leading to chemical-like brown spots or necrotic edges on foliage. This often occurs when plants are fertilized too frequently or when soil is not flushed periodically.
Check: Look for a white, crusty residue on the surface of the soil or the rim of the terracotta pot.
Fix: Flush the soil thoroughly with lukewarm water until it runs clear from the drainage holes, and switch to a more diluted fertilizing schedule during the growing season.
When to worry
You should take urgent action if the brown spots are expanding rapidly, smell foul, or are accompanied by a yellow halo, as these indicate a spreading fungal or bacterial infection.
Not sure which cause it is?
Upload a photo of your Monstera and get a diagnosis in seconds.
Diagnose my MonsteraYes, you can trim away the dead, brown parts of a leaf using clean scissors for aesthetic reasons, but be careful not to cut into the healthy green tissue.
This is almost always a sign of severe overwatering or temperature stress, as the tender new growth is highly susceptible to root-zone issues.
Misting provides only temporary relief and can encourage fungal issues if water sits on the leaves; it is better to use a humidifier or a pebble tray.
Consistent with guidance from: University of Florida IFAS Extension, Royal Horticultural Society.