Nitrogen Deficiency? (Yellowing Bottom Leaves)
Lower leaves yellowing first? Classic low-N sign, but pH or overwatering can mimic it.
Nitrogen deficiency in cannabis? Yellow bottom leaves—see causes and analyze fast.
Common Causes
- Low N in feed late veg
- Too much plain water flushing N
- pH off causing lockout
- Overwatering slowing uptake
How to Tell Which One You Have
Starts at bottom, moves up; veins pale too. Tops stay greener until severe.
FAQ
Can overwatering look like N deficiency?
Yes, poor uptake mimics low N.
Fix by heavy feeding?
Restore balanced N, don't spike EC.
Safe in late flower?
Mild fade is normal; severe yellow is not.
Browse problem guides
- Purple/Dark Leaves? (Phosphorus Deficiency)
- Brown Crunchy Edges? (Potassium Deficiency)
- Interveinal Yellowing? (Magnesium Deficiency)
- pH Lockout? (Leaves Pale But EC Fine)
- Salt Buildup? (High EC, Burnt Tips)
- Yellow New Growth? (Sulfur Deficiency)
- Yellow New Leaves, Green Veins? (Iron Deficiency)
- Speckled New Leaves? (Manganese Deficiency)