White spots on pot plant leaves are a common symptom that can come from several different issues. To identify the cause correctly, look at the pattern, texture, and location of the spots. Here is a detailed guide to the most likely causes and how to fix them.
How to identify
Looks like white, powdery dust on the leaf surface
Often starts on older leaves
Can spread quickly in humid, poorly ventilated spaces
Leaves may eventually yellow or curl
Why it happens
High humidity
Poor air circulation
Overcrowded plants
Cool nights + warm days
How to fix
Increase airflow around plants
Remove severely affected leaves
Avoid watering leaves; water soil only
Use a fungicidal spray (neem oil, potassium bicarbonate, sulfur spray)
How to identify
Tiny white or pale speckled dots on leaves (stippling)
Fine webbing underneath leaves
Leaves may look dusty or faded
Usually worse in hot, dry conditions
How to fix
Rinse leaves with water
Use neem oil or insecticidal soap
Increase humidity slightly (spider mites hate moisture)
Inspect neighboring plants
How to identify
Spots appear chalky, dry, and irregular
Often occur after misting or splashing water
No spreading or leaf damage
How to fix
Stop spraying tap water on leaves
Use filtered or rainwater
Wipe leaves gently with a damp cloth
How to identify
White or bleached spots
Usually on the top leaves closest to the light
Often happens after moving a plant from shade to strong sun
Leaves may feel crispy
How to fix
Move plant to indirect light or lower grow lights
Increase distance from LED grow lights
Introduce stronger light gradually
(Not as common but possible)
How to identify
White patches accompanied by yellowing, stunted growth, or brittle leaves
Pattern is often uniform, not random
Possible deficiencies:
Calcium (white spots + leaf tip curling)
Magnesium (interveinal yellowing + pale spots)
How to fix
Use a balanced fertilizer
Add Cal-Mag supplement if needed
Check soil pH
How to identify
White, tan, or light gray spots with defined borders
Spots may turn darker in the center
May spread slowly but consistently
How to fix
Remove infected leaves
Improve airflow
Keep foliage dry
Apply a garden-safe fungicide
Hangzhou Hongtai Electrical Appliance Co., Ltd.
info@seedmaxtech.com
